JP2008095091A - Phosphor and production method therefor, phosphor-containing composition, light emitting device, image display device and lighting device - Google Patents

Abstract

A highly practical phosphor manufacturing method capable of obtaining a SiON phosphor having a single phase and excellent luminous efficiency is provided.
A phosphor made of oxysilicon nitride is manufactured by performing at least a step of mixing silicate and Si ₃ N ₄ and firing in a reducing atmosphere.
[Selection figure] None

Description

  The present invention relates to a phosphor that emits fluorescence in a wavelength range from green to green-yellow (hereinafter abbreviated as “green / green-yellow” as appropriate), a method for producing the same, a phosphor-containing composition and a light-emitting device using the phosphor The present invention also relates to an image display device and an illumination device using the light emitting device. More specifically, a phosphor made of a rare earth-activated oxysilicon nitride that can be used for white light emitting diodes, fluorescent lamps, displays, etc., that emits visible light when excited by ultraviolet rays, visible light, electron beams, heat, or the like. The present invention also relates to a phosphor-containing composition and a light-emitting device using the phosphor, and an image display device and an illumination device using the light-emitting device.

White light emitting diodes are used for general illumination or for backlights of liquid crystal displays.
Most of the white light-emitting diodes currently in practical use have a structure in which a blue light-emitting diode is coated with a yellow phosphor. As the yellow phosphor, (Y, Gd) ₃ (Al, Ga) ₅ O ₁₂ : Ce Those represented by the composition formula (hereinafter sometimes abbreviated as “YAG phosphor”) are often used.

In addition to these, sialon phosphors, composition formula MSi ₂ O ₂ N ₂ : Eu ²⁺ (“M” in this specification represents a divalent metal element unless otherwise specified. , A phosphor having a basic composition represented by (hereinafter abbreviated as “SiON phosphor”), which is at least one element selected from the group consisting of Ca, Sr, and Ba. It is known as a phosphor that emits blue-green or yellow-red light when excited with blue light (see Patent Document 1, etc.).

These phosphors can be excited not only by blue light but also by violet or near ultraviolet rays, and exhibit higher light output than these YAG phosphors for these excitation lights.
Although sialon phosphors are usually synthesized in a high-pressure nitrogen atmosphere, it has been reported that SiON phosphors can be synthesized in a reducing atmosphere at normal pressure.
As a method for synthesizing the SiON phosphor, for example, a stoichiometric ratio of M ₃ N ₂ , Si ₃ N ₄ , SiO ₂ , and Eu ₂ O ₃ is sufficiently mixed, and this mixture is subjected to a normal pressure ammonia atmosphere. A technique of heating at a temperature of 1450 ° C. or 1500 ° C. for 5 hours has been reported (see Patent Document 2 and Patent Document 3).

However, in the conventional synthesis methods described in Patent Documents 1 to 3 (since these are fired in one stage by mixing raw materials, they may be referred to as “one-stage synthesis methods” as appropriate), SrCO ₃ (actual First, SrO) generated by thermal decomposition and SiO ₂ react with each other leaving Si ₃ N ₄ to produce stable SrSiO ₃ as a by-product. Therefore, at a firing temperature of about 1400 ° C., a by-product represented by the composition formula M _1-y Eu _y SiO ₃ is generated. For this reason, the obtained phosphor is not a single phase and has a problem in terms of luminous efficiency.

On the other hand, as a synthesis method when M is Sr, it has been reported that a single-phase phosphor can be obtained by using only SrO and Si ₃ N ₄ without using SiO ₂ as a raw material. Yes (see Non-Patent Document 1).
However, in the synthesis method of Non-Patent Document 1, it is considered that unreacted raw materials remain in addition to the desired MSi ₂ O ₂ N ₂ , judging from the ratio of the charged amounts of the respective raw materials.

The X-ray diffraction pattern of the SiON phosphor when M is Sr or Ba is described in Patent Document 3, and the X-ray diffraction pattern of the SiON phosphor when M is Ca _0.5 Sr _0.5 is not patented. Reference 1 describes each.
JP 2004-134805 A JP 2004-189996 A JP 2004-210921 A YQ Li, ACA Delsing, G. de With, and HT Hintzen, Chem. Mater., 17 (12), 3242-3248, 2005.

For any possible use such as a white light emitting diode, improvement of the luminous efficiency of the phosphor is strongly demanded. Further, with respect to white color tone, the color rendering properties of conventional light emitting diodes are insufficient, and a phosphor that emits light in the orange or red region is desired.
The SiON phosphor can maintain the same crystal structure over a wide range even if the kind and ratio of the alkaline earth element which is a constituent element is changed. Further, even if the concentration of the luminescent ions is increased, the luminous efficiency does not decrease so much, so that the concentration of the luminescent ions can be widely changed.

For this reason, the SiON phosphor has a composition capable of changing the emission color in a yellow to yellow-orange emission region for constituting a white light emitting diode. Specifically, (Sr _(1-x) M ^I _x ) _(1-y) M ^II _y Si ₂ N ₂ O ₂ (where M ^I is a divalent and / or trivalent atom other than Sr. M ^II represents one or more rare earth elements, and x and y represent numbers satisfying 0 ≦ x ≦ 1 and 0 <y ≦ 1, respectively. The composition represented.

With respect to these compositions, a synthesis method capable of obtaining a single phase at a temperature that can be realized by a reducing atmosphere furnace having a general molybdenum silicide heating element, for example, 1400 ° C., is realized. It has been demanded to obtain a phosphor having higher luminous efficiency than the phosphor obtained by the above method.
The present invention has been made in view of the above-described problems, and its purpose is to provide a highly practical phosphor manufacturing method capable of obtaining a SiON phosphor having a single phase and excellent luminous efficiency, and To provide a novel SiON phosphor having a single phase and excellent luminous efficiency, a phosphor-containing composition and a light-emitting device using the phosphor, an image display device using the light-emitting device, and It is to provide a lighting device.

As a result of studying the above problems, the present inventors have mixed SiO ₃ and Si ₃ N ₄ and calcined them in a reducing atmosphere, thereby having a single phase and excellent emission efficiency. It was found that a phosphor was obtained, and that the obtained SiON phosphor exhibited a characteristic powder X-ray diffraction pattern and was a phosphor having a novel crystal structure. Furthermore, the inventors have found that this phosphor exhibits very excellent characteristics as a light source in the light emission region from green to yellow-green, and found that the phosphor can be suitably used for applications such as light-emitting devices, thereby completing the present invention.

That is, the gist of the present invention is a method for producing a phosphor made of oxysilicon nitride, comprising a step of mixing silicate and Si ₃ N ₄ and firing in a reducing atmosphere. The present invention resides in a phosphor manufacturing method.
Here, it is preferable that the oxysilicon nitride has a composition represented by the following general formula [1].

(In the general formula [1], M ^I represents one or more metal elements capable of taking a divalent and / or trivalent valence other than Sr. M ^II represents one or more rare earth elements. X and y represent numbers satisfying 0 ≦ x ≦ 1 and 0 <y ≦ 1, respectively.
Moreover, it is preferable that the silicate has a composition represented by the following general formula [2].

(In the general formula [2], M ^I represents one or more metal elements capable of taking a divalent and / or trivalent valence other than Sr. M ^II represents one or more rare earth elements. X and y represent numbers satisfying 0 ≦ x ≦ 1 and 0 <y ≦ 1, respectively.
Moreover, it is preferable to further include a step of obtaining a silicate having the composition of the general formula [2] by mixing and firing at least a M ^I source, a M ^II source, and a Si source (Claim 4).

Moreover, it is preferable to use a flux at the time of baking (Claim 5).
Another gist of the present invention is that the composition has the composition represented by the general formula [1], and the powder X-ray diffraction pattern using CuKαX rays has a diffraction angle 2θ of 30 ° or more and 33 ° or less. When the intensity of the diffraction line with the highest intensity is 100%, the diffraction angle 2θ is 11 ° or more and 14 ° or less, the intensity of the diffraction line with the highest intensity is 50% or more, and the diffraction angle 2θ is 23. The intensity of a diffraction line having the highest intensity existing at an angle of not less than 27 ° and not more than 27 ° is 200% or more, and the intensity of other diffraction lines is 50% or less. Item 6).

Here, in the general formula [1], x is preferably less than 1. (Claim 7)
In the general formula [1], M ^II preferably contains at least Eu.
Another gist of the present invention resides in a phosphor-containing composition comprising the above-mentioned phosphor and a liquid medium (claim 9).

Another gist of the present invention includes a first light emitter and a second light emitter that emits visible light by irradiation of light from the first light emitter, and the second light emitter comprises: It exists in the light-emitting device characterized by containing at least 1 sort (s) or more of said fluorescent substance as 1st fluorescent substance (Claim 10).
Here, it is preferable that the second phosphor includes at least one phosphor having a light emission wavelength different from that of the first phosphor as the second phosphor.

The first light emitter has a light emission peak in a wavelength range of 420 nm or more and 500 nm or less, and the second light emitter is a light emission peak in a wavelength range of 570 nm or more and 680 nm or less as the second phosphor. It is preferable to contain at least one kind of phosphor having the above (claim 12).
In addition, the first light emitter has a light emission peak in a wavelength range of 300 nm to 420 nm, and the second light emitter has a light emission peak in a wavelength range of 420 nm to 490 nm as the second phosphor. It is also preferable to contain at least one kind of phosphor having an emission peak and at least one kind of phosphor having an emission peak in a wavelength range of 570 nm or more and 680 nm or less (claim 13).

The first light emitter has a light emission peak in a wavelength range of 420 nm or more and 500 nm or less, and the second light emitter is a light emission peak in a wavelength range of 580 nm or more and 620 nm or less as the second phosphor. It is also preferable to contain at least one phosphor having the formula (Claim 14).
According to another aspect of the present invention, there is provided an image display device comprising the above light-emitting device as a light source.

  Another gist of the present invention resides in an illumination device comprising the above-described light-emitting device as a light source (claim 16).

According to the phosphor production method of the present invention, a SiON phosphor having a single phase and excellent luminous efficiency can be obtained.
The phosphor of the present invention is a phosphor that exhibits a characteristic powder X-ray diffraction pattern and has a novel crystal form.
Moreover, by using the composition containing the phosphor of the present invention, a light-emitting device having high efficiency and high characteristics can be obtained. This light-emitting device is suitably used for an image display device or a lighting device.

Hereinafter, the present invention will be described in detail, but the present invention is not limited to the following description, and various modifications can be made within the scope of the gist thereof.
The relationship between the color name and chromaticity coordinates in the specification is based on the JIS standard (JISZ8110).
Further, in the composition formula of the phosphors in this specification, each composition formula is delimited by a punctuation mark (,). In addition, when a plurality of elements are listed by separating them with commas (,), one or two or more of the listed elements may be contained in any combination and composition. However, the total of the elements shown in parentheses is 1 mol. For example, the composition formula “(Ba, Sr, Ca) Al ₂ O ₄ : Eu” is expressed by “BaAl ₂ O ₄ : Eu”, “SrAl ₂ O ₄ : Eu”, and “CaAl ₂ O ₄ : Eu”. If: the _{"Ba 1-x Sr x Al 2} O 4 Eu ": the _{"Ba 1-x Ca x Al 2} O 4 Eu ": a _{"Sr 1-x Ca x Al 2} O 4 Eu " _{"Ba 1-xy Sr x Ca y} Al 2 O 4: Eu " and all assumed to generically indicated (in the above formula, 0 <x <1,0 <y <1,0 <x + y <1.)
[1. Phosphor]
[1-1. (Features of phosphor)
The phosphor of the present invention is expected to be used as a phosphor having light emission from green to green-yellow (hereinafter abbreviated as “green / green-yellow phosphor” as appropriate), and has the following characteristics. .

<Composition>
The phosphor of the present invention has a composition represented by the following general formula [1].

In the general formula [1], M ^I represents one or more metal elements that can have a divalent and / or trivalent valence other than Sr.
Examples of M ^I include an alkaline earth metal element and an element having an electronegativity and an ion radius close to those of the alkaline earth metal element.
Specifically, preferable examples of the divalent element include calcium (Ca), barium (Ba), zinc (Zn), and magnesium (Mg), and preferable examples of the trivalent element include scandium (Sc). , Yttrium (Y), lanthanum (La), gadolinium (Gd), and ruthenium (Lu).

However, the molar ratio of the divalent element to (the sum of the divalent element and the trivalent element) relative to the entire M ^I is usually 0.5 or more, preferably 0.7 or more, more preferably 0.8 or more, Moreover, although it is 1 or less normally, it is so preferable that it is close to 1. If the molar ratio of the divalent element to the entire M ^I is too low, the luminous efficiency tends to decrease. This is because a divalent element and a trivalent element are taken into the crystal lattice, but it is considered that the trivalent element absorbs emission energy in the crystal.

Among these, as M ^I , an alkaline earth metal element is preferable. Specifically, Ca and Ba are preferable and Ba is particularly preferable from the viewpoint of the luminous efficiency of the obtained phosphor.
As M ^I , any one of the above-exemplified elements may be used alone, or two or more may be used in combination in any ratio and combination.
In the general formula [1], M ^II is intended listed as activation element represents one or more rare earth elements.

Specific examples of rare earth elements include Eu, Sm, Tm, Yb and the like. Among these, Sm, Eu, and Yb are preferable and Eu is particularly preferable from the viewpoint of the luminous efficiency of the phosphor.
The M ^II, may be used either singly exemplified above elements may be used in combination of two or more in optional ratio and combination.
Among them, M ^II preferably includes at least Eu, more preferably has a molar ratio of Eu to the entire M ^II of 0.7 or more, and particularly preferably all of M ^II is Eu.

Formula [1] in, x is a number that indicates the molar ratio of M ^I to the total amount of Sr and M ^I, a number satisfying 0 ≦ x ≦ 1. if x is 0, the phosphor of the present invention do not contain M ^I, when x is 1, the phosphor of the present invention will not contain Sr.
Specifically, the lower limit value of x is usually 0 or more, preferably 0.1 or more.
On the other hand, the upper limit of x is usually 1 or less, preferably less than 1, more preferably 0.9 or less, and still more preferably 0.8 or less. If the value of x is too large, the emission intensity may decrease.

Formula [1] in, y is, Sr, is a number that indicates the molar ratio of M ^II to the total amount of M ^I, and M ^II, is a number satisfying 0 <y ≦ 1. When y is 1, the phosphor of the present invention will not contain Sr and M ^I.
Specifically, the lower limit value of y is usually larger than 0, preferably 0.01 or more, more preferably 0.02 or more. If the value of y is too small, the concentration of luminescent center ions will be low, and the luminescence intensity may not be high.

On the other hand, the upper limit of y is usually 1 or less, preferably 0.6 or less, more preferably 0.4 or less, and still more preferably 0.2 or less. If the value of y is too large, concentration quenching may occur.
The phosphor of the present invention is not limited to the elements described in the general formula [1], that is, M ^I , M ^II , Sr (strontium), Si (silicon), O (oxygen), and N (nitrogen). Furthermore, an element selected from the group consisting of a monovalent element, a divalent element, a trivalent element, a −1 valent element, and a -3 valent element (hereinafter referred to as “flux element” as appropriate) is contained. You may do it.

  Among them, the flux elements include alkali metal elements, alkaline earth metal elements, zinc (Zn), yttrium (Y), aluminum (Al), scandium (Sc), phosphorus (P), rare earth elements, and halogen elements. It preferably contains one element selected from the group. The phosphor of the present invention may contain any one of them alone, or may contain two or more kinds in any combination and ratio.

The total content of the above flux elements is usually 1 ppm or more, preferably 3 ppm or more, more preferably 5 ppm or more, and usually 100 ppm or less, preferably 50 ppm or less, more preferably 30 ppm or less. When the phosphor of the present invention contains a plurality of types of flux elements, the total amount thereof satisfies the above range.
<Characteristics concerning powder X-ray diffraction spectrum>
In the powder X-ray diffraction pattern using CuKα X-rays, the phosphor of the present invention has the highest intensity diffraction line having a diffraction angle 2θ of 30 ° or more and 33 ° or less (hereinafter referred to as “reference diffraction line” as appropriate). .)) When the strength is 100%, all the following conditions (i) to (iii) are satisfied.
(I) The intensity of the highest-intensity diffraction line existing at a diffraction angle 2θ of 11 ° or more and 14 ° or less (hereinafter referred to as “first specific diffraction line” as appropriate) is usually 50% or more, preferably 100 % Or more, more preferably 200% or more, and still more preferably 300% or more.
(Ii) The intensity of the diffraction line with the highest intensity existing at a diffraction angle 2θ of 23 ° or more and 27 ° or less (hereinafter referred to as “second specific diffraction line” as appropriate) is usually 200% or more, preferably 300. % Or more, more preferably 400% or more, still more preferably 500% or more.
(Iii) The intensity of all other diffraction lines excluding the reference diffraction line, the first specific diffraction line, and the second specific diffraction line is usually 50% or less, preferably 40% or less, more preferably 30% or less. is there.

That is, the phosphor of the present invention is characterized in that the above-mentioned reference diffraction line, first specific diffraction line, and second specific diffraction line are very large compared to the intensity of other diffraction lines.
The range of the diffraction angle 2θ (11 ° ≦ 2θ ≦ 14 °) in which the first specific diffraction line is observed corresponds to a range where the surface interval d is 8.037Å ≧ d ≧ 6.321Å.
The range of the diffraction angle 2θ in which the second specific diffraction line is observed (23 ° ≦ 2θ ≦ 27 °) corresponds to a range where the surface interval d is 3.864３ ≧ d ≧ 3.300３.

Here, the surface interval d corresponding to the first specific diffraction line corresponds to the lattice constant of the phosphor of the present invention, and the surface interval d corresponding to the second specific diffraction line takes half the value of the lattice constant. it is conceivable that.
In addition, although the crystal structure of the phosphor of the present invention is layered, it is considered that the first specific diffraction line and the second specific diffraction line are due to a plane parallel to the layer.
Further, the phosphor of the present invention is preferably as the crystallite diameter is larger. Here, the crystallite diameter can be obtained by measuring a half width in powder X-ray diffraction. It is believed that non-radiative deactivation occurs at the interface between crystallites, and conversion of luminescence energy into thermal energy occurs. When the crystallite is large, the crystallite interface is reduced, so that the conversion to heat energy is small and the luminance is increased.

<Characteristics related to emission spectrum>
In view of the use as a green-yellow phosphor, the phosphor of the present invention preferably has the characteristics described below when an emission spectrum obtained by excitation with blue light having a wavelength of 430 to 470 nm is measured.
The emission peak wavelength λp (nm) in the emission spectrum is usually in the range of 525 nm or more, especially 530 nm or more, and usually 600 nm or less, especially 590 nm or less. If the emission peak wavelength λp is too short, it tends to be greenish, whereas if it is too long, it tends to be reddish.

  Further, the full width at half maximum (hereinafter referred to as “FWHM” where appropriate) of the emission peak in the emission spectrum is usually 75 nm or more, particularly 80 nm or more, more preferably 82 nm or more, and usually 89 nm or less. In particular, it is preferably 88 nm or less, more preferably 86 nm or less. The wide half-value width FWHM of the broad emission peak is expected to have high luminance, and further, the emission spectrum can be spread over the entire visible light region required for white illumination.

In order to excite the phosphor of the present invention with blue light having a wavelength of 430 to 470 nm, for example, light having a wavelength of 460 nm, for example, a GaN-based light emitting diode can be used.
Moreover, the measurement of the emission spectrum of the phosphor of the present invention and the calculation of the emission peak wavelength, peak relative intensity and peak half-value width can be carried out using an apparatus such as a fluorescence measuring apparatus manufactured by JASCO Corporation.

<Characteristics related to excitation wavelength>
The excitation wavelength of the phosphor of the present invention is not particularly limited, but when the excitation spectrum is measured at any of the emission wavelengths of 525 to 600 nm, it usually has an excitation peak in the wavelength range of 230 nm or more and 470 nm or less. Among them, it is more preferable to always emit light even when excited with any light within the wavelength range. That is, since the phosphor of the present invention can be excited by light in the blue region and / or light in the near ultraviolet region, the phosphor of the present invention is preferably used for a light emitting device using a semiconductor light emitting element or the like as the first light emitter. Can do.

The excitation spectrum is measured at room temperature, for example, 25 ° C., with a 150 W xenon lamp as the excitation light source, and a fluorescence measurement apparatus (manufactured by JASCO Corporation) equipped with a multi-channel CCD detector C7041 (manufactured by Hamamatsu Photonics) as the spectrum measurement apparatus. Can be measured. The excitation peak wavelength can be calculated from the obtained excitation spectrum.
<Weight median diameter>
The phosphor of the present invention preferably has a weight median diameter in the range of usually 5 μm or more, especially 10 μm or more, and usually 30 μm or less, especially 20 μm or less. When the weight median diameter is too small, the luminance is lowered and the phosphor particles tend to aggregate. On the other hand, if the weight median diameter is too large, there is a tendency for coating unevenness and blockage of a dispenser or the like to occur.

The weight median diameter of the phosphor of the present invention can be measured using a device such as a laser diffraction / scattering particle size distribution measuring device.
<Others>
The phosphor of the present invention is more preferable as its internal quantum efficiency is higher. The value is usually 0.5 or more, preferably 0.6 or more, more preferably 0.7 or more. If the internal quantum efficiency is low, the light emission efficiency tends to decrease.

The phosphor of the present invention is preferably as its absorption efficiency is high. The value is usually 0.5 or more, preferably 0.6 or more, more preferably 0.7 or more. When the absorption efficiency is low, the light emission efficiency tends to decrease.
[1-2. (Method for producing phosphor)
The method for producing the phosphor of the present invention is not particularly limited, but a method having a step of mixing silicate and Si ₃ N ₄ and firing in a reducing atmosphere (hereinafter referred to as “production of phosphor of the present invention”). It is preferably produced by the “method” or simply “the production method of the present invention”).

Here, the kind of silicate mixed with Si ₃ N ₄ is not particularly limited, but usually a multi-component silicate represented by the following general formula [2] is preferably used.

In the general formula [2], M ^I , M ^II , x and y each represent the same definition as in the general formula [1]. The details of preferred specific examples are also described in [I-1. As described in [Features of phosphor].
The production method of the present invention is usually performed by the following steps.
First, in the above general formula [1], a raw material of Sr (hereinafter referred to as “Sr source” as appropriate), a raw material of metal element M ^I (hereinafter referred to as “M ^I source” as appropriate), and a raw material of Si (hereinafter referred to as “ And a raw material of the element M ^II which is an activating element (hereinafter referred to as “M ^II source” where appropriate) (this step is referred to as “primary mixing step”) to obtain. By firing the mixture (this step is referred to as “primary firing step”), a multi-component silicate having a composition represented by the above general formula [2] is obtained.

Next, the obtained multi-component silicate and Si ₃ N ₄ are mixed (this step is referred to as “secondary mixing step”), and the mixture is fired again in a reducing atmosphere to achieve the target. The phosphor of the present invention is obtained (this step is referred to as “secondary firing step”).
In addition to the above raw materials, a flux or the like is further mixed as necessary. The flux may be mixed in the primary mixing step, but is preferably mixed in the secondary mixing step.

<Raw material>
Examples of the Sr source, M ^I source, Si source, and M ^II source used in the production of the phosphor of the present invention include oxides, hydroxides, carbonates, nitrates of M ^I , Si, and M ^II elements. , Sulfate, oxalate, carboxylate, halide and the like. From these compounds, the reactivity to the composite oxide, the low generation amount of NO _x , SO _{x and the} like during firing may be selected as appropriate.

Specific examples of the Sr source include SrO, Sr (OH) ₂ .8H ₂ O, SrCO ₃ , Sr (NO ₃ ) ₂ , SrSO ₄ , Sr (OCO) ₂ .H ₂ O, Sr (OCOCH ₃ ) _2. 0.5H ₂ O, SrCl _{2 and the} like can be mentioned. Of these, SrCO ₃ , SrCl _{2 and the} like are preferable.
Any one of these Sr sources may be used alone, or two or more thereof may be used in any combination and ratio.

Specific examples of the M ^I source are listed for each type of M ^I metal as follows.
Specific examples of the Ba source include BaO, Ba (OH) ₂ .8H ₂ O, BaCO ₃ , Ba (NO ₃ ) ₂ , BaSO ₄ , Ba (OCO) ₂ .2H ₂ O, Ba (OCOCH ₃ ) ₂ , BaCl _2, and the like. Of these, BaCO ₃ , BaCl _{2 and the} like are preferable.
Specific examples of the Ca source include CaO, Ca (OH) ₂ , CaCO ₃ , Ca (NO ₃ ) ₂ .4H ₂ O, CaSO ₄ .2H ₂ O, Ca (OCO) ₂ .H ₂ O, Ca (OCOCH ₃ ) ₂ · H ₂ O, CaCl _{2 and the} like. Of these, CaCO ₃ , CaCl _{2 and the} like are preferable.

Specific examples of the Zn source include ZnO, Zn (C ₂ O ₄ ) · 2H ₂ O, ZnSO ₄ · 7H ₂ O, and the like.
Specific examples of the Mg source include MgCO ₃ , MgO, MgSO ₄ , Mg (C ₂ O ₄ ) · 2H ₂ O, and the like.
Any one of these ^MI sources may be used alone, or two or more thereof may be used in any combination and ratio.

Specific examples of the Si source include SiO ₂ , H ₄ SiO ₄ , Si (OCOCH ₃ ) _{4 and the} like. Of these, SiO ₂ is preferable.
One of these Si sources may be used alone, or two or more thereof may be used in any combination and ratio.
Among the M ^II sources, specific examples of Eu sources include Eu ₂ O ₃ , Eu ₂ (SO ₄ ) ₃ , Eu ₂ (OCO) ₆ , EuCl ₂ , EuCl ₃ , Eu (NO ₃ ) ₃ .6H ₂ O. Etc. Of these, Eu ₂ O ₃ , EuCl _{2 and the} like are preferable.

Specific examples of the Sm source, the Tm source, the Yb source, and the like include compounds in which Eu is replaced with Sm, Tm, Yb, etc. in the respective compounds listed as specific examples of the Eu source.
Any one of these ^MII sources may be used alone, or two or more thereof may be used in any combination and ratio.
Moreover, you may use the compound containing another element as a raw material according to the composition of the fluorescent substance of this invention made into the objective. For example, when producing a phosphor composition containing Ge, as a specific example of a Ge _{source, GeO 2, Ge (OH)} 4, Ge (OCOCH 3) 4, GeCl 4 , and the like. Of these, GeO _{2 and the} like are preferable.

Any one of these compounds containing other elements may be used alone, or two or more may be used in any combination and ratio.
<Primary mixing process>
First, in the primary mixing step, the above-described Sr source, M ^I source, Si source and M ^II source, and other raw materials used as necessary are mixed. The mixing method is not particularly limited, but examples include the following methods (A) and (B).
(A) Dry pulverizer such as hammer mill, roll mill, ball mill, jet mill, etc., or pulverization using mortar and pestle, etc. and mixer such as ribbon blender, V-type blender, Henschel mixer, or mortar and pestle A dry mixing method in which raw materials such as Sr source, M ^I source, Si source and M ^II source are pulverized and mixed in combination with mixing.
(B) Add a solvent or dispersion medium such as water to raw materials such as Sr source, M ^I source, Si source and M ^II source, and mix using a pulverizer, mortar and pestle, or evaporating dish and stirring rod, A wet mixing method in which a solution or slurry is made and then dried by spray drying, heat drying, or natural drying.

<Primary firing process>
Next, firing (primary firing) is performed on a mixture of raw materials such as Sr source, M ^I source, Si source and M ^II source obtained in the primary mixing step (hereinafter sometimes referred to as “primary mixture”). Do.
The primary firing is usually performed by putting the primary mixture obtained in the above-described primary mixing step into a heat-resistant container such as a crucible or a tray made of a material that has low reactivity with each raw material and heating.

The temperature during primary firing is usually in the range of 800 ° C. or higher, preferably 850 ° C. or higher, more preferably 950 ° C. or higher, and usually 1300 ° C. or lower, preferably 1250 ° C. or lower. If the firing temperature is too low, the crystals may not grow sufficiently and the particle size may be small. On the other hand, if the firing temperature is too high, the crystals may grow too much and the particle size may become too large.
Although the pressure at the time of primary firing varies depending on the firing temperature or the like, it is usually at or above normal pressure.

The primary firing time varies depending on the firing temperature and pressure, but is usually 10 minutes or longer, preferably 1 hour or longer, and usually 24 hours or shorter, preferably 3 hours or shorter.
The atmosphere during primary firing is not particularly limited, but in the present invention, firing is preferably performed in an atmosphere having a low oxygen concentration, as will be described later.
Specifically, the oxygen concentration at the time of primary firing is preferably 100 ppm or less, more preferably 50 ppm or less, and particularly preferably 20 ppm or less. Ideally, no oxygen is present at all. As a specific example, it is carried out in a single atmosphere or a mixed atmosphere of two or more of gases such as carbon monoxide, carbon dioxide, nitrogen, hydrogen, and argon. Among these, it is preferable to contain reducing gas, such as carbon monoxide and hydrogen, and especially in a hydrogen-containing nitrogen atmosphere.

Moreover, it is preferable to make solid oxygen mentioned later coexist in a reaction system in the case of primary baking, and to reduce oxygen concentration and to make it a strong reducing atmosphere.
<Secondary mixing process>
A multi-component silicate represented by the compositional formula {(Sr _(1-x) M ^I _x ) _(1-y) M ^II _y } ₂ SiO ₄ is obtained as a product of the above-described primary firing step. The product obtained by this primary firing step is usually pulverized with a ball mill or the like and then mixed with Si ₃ N ₄ .

The mixing method is not particularly limited, and examples thereof include the methods (A) and (B) described in the section of <Primary mixing step> above.
<Secondary firing process>
Next, firing (secondary firing) is performed on the mixture obtained in the secondary mixing step, such as a multi-component silicate and Si ₃ N ₄ (hereinafter sometimes referred to as “secondary mixture”).

The secondary firing is usually performed by putting the secondary mixture obtained in the above-described secondary mixing step into a heat-resistant container such as a crucible or a tray made of a material having low reactivity with each raw material and heating.
The temperature during secondary firing is usually in the range of 1100 ° C or higher, preferably 1200 ° C or higher, more preferably 1300 ° C or higher, and usually 1500 ° C or lower, preferably 1400 ° C or lower. If the firing temperature is too low, the crystals may not grow sufficiently and the particle size may be small. On the other hand, if the firing temperature is too high, the crystals may grow too much and the particle size may become too large.

The pressure at the time of secondary firing varies depending on the firing temperature or the like, but is usually at or above normal pressure.
The time of secondary firing varies depending on the temperature and pressure at the time of firing, but usually 1 hour or more, preferably 2 hours or more, and usually 24 hours or less, preferably 10 hours or less, more preferably 8 hours or less. It is a range.
The atmosphere during the secondary firing is not particularly limited, but in the present invention, firing is preferably performed in an atmosphere having a low oxygen concentration as described above.

  Specifically, the oxygen concentration at the time of secondary firing is preferably 100 ppm or less, more preferably 50 ppm or less, and particularly preferably 20 ppm or less. Ideally, no oxygen is present at all. As a specific example, it is carried out in a single atmosphere or a mixed atmosphere of two or more of gases such as carbon monoxide, carbon dioxide, nitrogen, hydrogen, and argon. Among these, it is preferable to contain reducing gas, such as carbon monoxide and hydrogen, and especially under a nitrogen atmosphere containing hydrogen.

Moreover, it is preferable to make the oxygen concentration lower and make it in a strongly reducing atmosphere by coexisting solid carbon, which will be described later, in the reaction system also during the secondary firing.
<Solid carbon>
To produce the phosphor of the present invention, as the activation element M ^II of the present invention is to contribute ionic state into luminescence (valence), select the required atmosphere. For example, it is desirable that at least a part of Eu as an activating element, which is one of preferable M ^II elements that cause green light emission in the phosphor of the present invention, be a divalent ion. Specifically, the ratio of Eu ²⁺ in the total Eu is preferably as high as possible, and is usually 50% or more, preferably 80% or more, more preferably 90% or more, and most preferably 95% or more. However, a compound containing trivalent Eu ions such as Eu ₂ O ₃ is usually used as a raw material for Eu. Therefore, in order to obtain a phosphor that contains Eu ²⁺ that is a divalent ion and produces green light emission, conventionally, in order to reduce the trivalent ion Eu ³⁺ to the divalent ion Eu ²⁺ , carbon monoxide, It was common to calcinate in some reducing atmosphere such as nitrogen / hydrogen or hydrogen. However, even in these firing atmospheres, oxygen derived from raw materials and the like is contained, so that it has been difficult to sufficiently reduce the oxygen concentration. Further, when Sm, Tm, Yb or the like is used as the M ^II element, there are the same problems as in the case of Eu described above.

As a result of the study, the inventors reduced the trivalent ion of the M ^II element to a divalent ion and simultaneously introduced it into the host crystal, and then calcined under the condition of coexisting solid carbon in addition to the normal reducing atmosphere. It has been found that it is effective to perform (primary firing step and / or secondary firing step). As a result, the obtained phosphor has the characteristics that it emits light with high brightness in the wavelength range of 525 nm or more and 600 nm or less as described above, and at the same time, the emission spectrum width is narrow.

The type of solid carbon is not particularly limited, and any type of solid carbon can be used. Examples thereof include carbon black, activated carbon, pitch, coke, graphite, etc. Among them, activated carbon is preferable. The shape of the solid carbon includes a bead shape and a block shape, but is not particularly limited.
The amount of solid carbon to be coexisted depends on other firing conditions, but the mixture to be fired (primary mixture in the case of the primary firing step, secondary mixture in the case of the secondary firing step, hereinafter abbreviated as “baking raw material”) Is usually 0.1% by weight or more, preferably 1% by weight or more, more preferably 10% by weight or more, particularly preferably 30% by weight or more, and most preferably 50% by weight or more.

Further, by using a graphite crucible as a firing container, it is possible to obtain the same effect as the coexistence of solid carbon. On the other hand, when a crucible made of a material other than carbon such as an alumina crucible is used, it is preferable that solid carbon such as graphite beads, granules and blocks coexist separately.
Note that firing is preferably performed under sealed conditions, such as by covering the crucible.

  Note that firing in the presence of solid carbon means that the phosphor raw material and solid carbon need only exist in the same firing container, and it is necessary to mix and fire the phosphor raw material and solid carbon. Absent. Generally, when carbon is mixed in a phosphor product, the black carbon absorbs the light emission of the phosphor, so that the luminous efficiency of the phosphor decreases. As an example of the method of coexisting solid carbon, put solid carbon in a container different from the container containing the firing raw material, and place these containers in the same crucible (for example, the upper part of the firing raw material container (So that the container is positioned), a container containing solid carbon is embedded in the firing raw material, or conversely, solid carbon is placed around the container filled with the firing raw material powder. . In addition, when using a large crucible, it is preferable to sinter solid carbon in the same container as a calcination raw material. In any case, the solid carbon is devised so as not to be mixed in the phosphor raw material.

As a technique for obtaining a divalent ion of the M ^II element, in addition to the above-described technique for coexisting solid carbon, or in place of the technique for coexisting solid carbon, the following technique can also be implemented. That is, it is preferable to remove the air present in the crucible at the same time as the raw material powder as much as possible to lower the oxygen concentration. As a specific method, it is preferable that the crucible charged with a predetermined raw material is removed under reduced pressure in a vacuum furnace, and an atmospheric gas used during firing is introduced to restore the pressure. It is more preferable to repeat this operation. Alternatively, an oxygen getter such as Mo can be used as necessary.

The presence of solid carbon in this manner is preferable because the oxygen concentration in the firing atmosphere can be reduced and the firing atmosphere can be reduced.
Solid carbon may be used only during the primary firing step, may be used only during the secondary firing step, or may be used in both the primary firing step and the secondary firing step, but at least the secondary firing step. It is preferably used during the process, and particularly preferably used in both the primary firing step and the secondary firing step.

<Flux>
In the production method of the present invention, it is preferable that a flux coexists in the reaction system from the viewpoint of growing good crystals.
The type of the flux is not particularly limited, but a compound containing a monovalent element or atomic group and a -1 valent element, a compound containing a monovalent element or atomic group and a -3 valent element or atomic group, A compound containing a divalent metal element and a -1 valent element, a compound containing a divalent element and a -3 valent element or an atomic group, a trivalent element and a -1 valent element It is preferable to use as the flux a compound selected from the group consisting of a compound and a compound containing a trivalent element and a -3 valent element or atomic group.

The monovalent element is preferably, for example, at least one element selected from the group consisting of an alkali metal element and an ammonium group (NH ₄ ), and more preferably cesium (Cs) or rubidium (Rb). .
The divalent element is preferably, for example, at least one element selected from the group consisting of an alkaline earth metal element and zinc (Zn), and more preferably strontium (Sr) or barium (Ba). preferable.

The trivalent element is preferably at least one element selected from the group consisting of rare earth elements such as lanthanum (La), yttrium (Y), aluminum (Al), and scandium (Sc). (Y) or aluminum (Al) is more preferable.
The -1 valent element is preferably, for example, at least one element selected from the group consisting of halogen elements, and is preferably chlorine (Cl) or fluorine (F).

The −3 element or atomic group is preferably, for example, a phosphate group (PO ₄ ).
Among the above, the flux is a trivalent selected from the group consisting of alkali metal halides, alkaline earth metal halides, zinc halides, yttrium (Y), aluminum (Al), scandium (Sc), and rare earth elements. Selected from the group consisting of elemental halides, alkali metal phosphates, alkaline earth metal phosphates, zinc phosphate, yttrium (Y), aluminum (Al), lanthanum (La), and scandium (Sc) It is preferable to use a compound selected from the group consisting of phosphates of trivalent elements.

More specifically, NH ₄ Cl, LiCl, NaCl, KCl, CsCl, CaCl ₂ , BaCl ₂ , SrCl ₂ , YCl ₃ .6H ₂ O (however, it may be an hydrate), ZnCl ₂ , MgCl ₂ .6H ₂ O (but may be hydrated), chlorides such as RbCl, LiF, NaF, KF, CsF, CaF ₂ , BaF ₂ , SrF ₂ , AlF ₃ , MgF ₂ , YF Examples thereof include fluorides such as _{3 and} phosphates such as KPO ₄ .

Among them, it is particularly preferable to use NH ₄ Cl.
These fluxes may be used singly or in combination of two or more in any combination and ratio, but the following effects can be obtained by using two or more in combination.
Although it varies depending on the type of flux, firing conditions, and the like, generally, when the flux is allowed to coexist in the phosphor material, crystal growth of the phosphor is promoted, and a phosphor having a large particle size tends to be obtained. In addition, the phosphor of the present invention tends to increase in luminance as the particle size increases. From the above, when the flux is allowed to coexist in the phosphor raw material, it seems that the brightness is improved, but it seems preferable. There is a tendency.

  The amount of flux used (the total amount used when two or more fluxes are used in combination) varies depending on the type of raw material, the material of the flux, the firing temperature, the atmosphere, etc., but is usually 0.01% by weight or more. Is preferably 0.1% by weight or more, usually 20% by weight or less, and more preferably 10% by weight or less. If the amount of flux used is too small, the effect of flux may not appear. If the amount of flux used is too large, the flux effect will be saturated, the particle size will become too large and the handleability will be poor, it will be incorporated into the host crystal and the emission color may be changed, and the brightness may be reduced. .

Moreover, when using in combination of 2 or more types of flux, the use ratio (molar ratio) of the compound containing a monovalent or trivalent element is 1 when the number of moles of the compound containing a divalent element is 1. It is usually 0.1 or more, preferably 0.2 or more, and usually 10 or less, preferably 5 or less.
Moreover, the timing in particular which mixes a flux with a reaction system is not restrict | limited, You may add at the time of a primary mixing process, and may add at the time of a secondary mixing process. Furthermore, you may add in multiple times. However, it is preferable to add the flux at least during the secondary mixing step and mix it so that the flux coexists in the reaction system during the secondary firing step.

<Post-processing>
After the above-described firing step, the phosphor of the present invention can be obtained by performing treatments such as washing, drying, and classification as necessary.
In addition, when manufacturing the light-emitting device by the method to be described later using the phosphor of the present invention, it is preferable to perform a known surface treatment, for example, calcium phosphate treatment, if necessary, before use.

[1-3. (Use of phosphor)
The phosphor of the present invention can be used for any application using the phosphor, and in particular, by utilizing the characteristic that it has excellent conversion efficiency for blue light or near ultraviolet light, various light emitting devices (described later). “Light-emitting device of the present invention”).
In particular, since the phosphor of the present invention is a green / green-yellow phosphor, when used in a light-emitting device that emits light in the wavelength range from green to green-yellow (hereinafter referred to as “green / green-yellow light-emitting device” as appropriate), it is highly efficient. A green / green yellow light emitting device can be realized.

  A high-performance white light emitting device can be realized by combining a phosphor of the present invention, which is a green / green-yellow phosphor, with a red phosphor, a blue phosphor, an orange phosphor, or the like. The luminescent color in this case can be changed to a desired luminescent color by adjusting the type and usage ratio of the phosphor of the present invention and the phosphor combined therewith. Further, for example, an emission spectrum similar to an emission spectrum of so-called pseudo white (for example, emission color of a light emitting device combining a blue LED and a yellow phosphor) can be obtained.

In addition, combining this white light-emitting device with a red phosphor (phosphor that emits red fluorescence) realizes a light-emitting device that excels in red color rendering and a light-emitting device that emits light bulb color (warm white). can do.
Even if the phosphor of the present invention is combined with a blue phosphor (a phosphor that emits blue fluorescence) and a red phosphor (a phosphor that emits red fluorescence) in combination with an excitation light source that emits near-ultraviolet light, white light is emitted. The device can be manufactured.

Of course, the light emission color of the light emitting device is not limited to white, and if necessary, a yellow phosphor (a phosphor that emits yellow fluorescence), a green phosphor (a phosphor that emits green fluorescence), a blue phosphor, A light emitting device that emits light in an arbitrary color can be manufactured by adjusting the type and use ratio of the phosphor by combining orange to red phosphors, other types of green phosphors, and the like.
The light-emitting device of the present invention thus obtained can be used, for example, as a light-emitting unit (particularly a liquid crystal backlight) or an illumination device of an image display device.

[1-4. Phosphor-containing composition
When the phosphor of the present invention is used for a light emitting device or the like, it is preferable to use the phosphor in a form dispersed in a liquid medium. The phosphor of the present invention dispersed in a liquid medium will be referred to as “the phosphor-containing composition of the present invention” as appropriate.
The liquid medium that can be used in the phosphor-containing composition of the present invention is a liquid medium that exhibits liquid properties under the desired use conditions, and that suitably disperses the phosphor of the present invention and does not cause undesirable reactions. Any one can be selected according to the purpose or the like. Examples of the liquid medium include a thermosetting resin and a photocurable resin before curing, and examples thereof include an addition reaction type silicone resin, a condensation reaction type silicone resin, a modified silicone resin, and an epoxy resin. Further, a solution obtained by hydrolytic polymerization of a solution containing an inorganic material, for example, a ceramic precursor polymer or a metal alkoxide by a sol-gel method can be used. These liquid media may be used individually by 1 type, and may use 2 or more types together by arbitrary combinations and a ratio. In addition, an organic solvent can be contained in the liquid medium.

  The amount of the liquid medium used may be appropriately adjusted according to the application, etc., but in general, the weight ratio of the liquid medium to the phosphor of the present invention is usually 3% by weight or more, preferably 5% by weight or more, Moreover, it is 30 weight% or less normally, Preferably it is the range of 15 weight% or less. If the amount of the liquid medium is too small, light emission from the phosphor becomes too strong and the luminance may be lowered. If too much, the light emission from the phosphor becomes too weak and the luminance may be lowered.

In addition to the phosphor of the present invention and the liquid medium, the phosphor-containing composition of the present invention may contain other optional components depending on its use and the like. Examples of other components include a diffusing agent, a thickener, a bulking agent, and an interference agent. Specifically, silica-based fine powder such as Aerosil, alumina and the like can be mentioned.
In addition, these other components may be used individually by 1 type, and may use 2 or more types together by arbitrary combinations and ratios.
[2. Light emitting device]
Next, the light emitting device of the present invention will be described. The light-emitting device of the present invention includes at least a first light-emitting body and a second light-emitting body that emits visible light when irradiated with light from the first light-emitting body.

[2-1. First luminous body]
The 1st light-emitting body in the light-emitting device of this invention light-emits the light which excites the 2nd light-emitting body mentioned later. The light emission wavelength of the first light emitter is not particularly limited as long as it overlaps with the absorption wavelength of the second light emitter described later, and a light emitter having a wide light emission wavelength region can be used. Usually, an illuminant having an emission wavelength from the near-ultraviolet region to the blue region is used, and specific values are usually 300 nm or more, preferably 330 nm or more, and usually 500 nm or less, preferably 480 nm or less. A luminescent material is used. At this time, light in the near-ultraviolet region is preferably light having a wavelength of 300 nm and 420 nm or less, and light in the blue region is preferably light having a wavelength of 420 nm and having a wavelength of 500 nm or less. As the first light emitter, a semiconductor light emitting element is generally used. Specifically, a light emitting diode (hereinafter abbreviated as “LED” as appropriate) or a semiconductor laser diode (semiconductor laser diode). Hereinafter, abbreviated as “LD” as appropriate) can be used. In addition, an organic electroluminescence light emitting element, an inorganic electroluminescence light emitting element, etc. can be used. However, of course, it is not restricted to these.

Among these, as the first light emitter, a GaN LED or LD using a GaN compound semiconductor is preferable. This is because GaN-based LEDs and LDs have significantly higher light emission output and external quantum efficiency than SiC-based LEDs that emit light in this region, and are extremely bright with very low power when combined with the phosphor. This is because light emission can be obtained. For example, for a current load of 20 mA, GaN-based LEDs and LDs usually have a light emission intensity 100 times or more that of SiC-based. A GaN-based LED or LD preferably has an Al _x Ga _Y N light emitting layer, a GaN light emitting layer, or an In _x Ga _Y N light emitting layer. Among GaN-based LEDs, those having an In _X Ga _Y N light-emitting layer are particularly preferable because the emission intensity is very strong, and in GaN-based LDs, the multiple quantum of the In _X Ga _Y N layer and the GaN layer is preferred. A well structure is particularly preferable because the emission intensity is very strong.

In the above, the value of X + Y is usually a value in the range of 0.8 to 1.2. In the GaN-based LED, those in which the light emitting layer is doped with Zn or Si or those without a dopant are preferable for adjusting the light emission characteristics.
A GaN-based LED has these light-emitting layer, p-layer, n-layer, electrode, and substrate as basic components, and the light-emitting layer is composed of n-type and p-type Al _x Ga _y N layers, GaN layers, or In _x. Those having a heterostructure sandwiched between Ga _Y N layers and the like have high luminous efficiency, and those having a heterostructure having a quantum well structure are further preferred because of higher luminous efficiency.

[2-1. Second light emitter]
The second light emitter in the light emitting device of the present invention is a light emitter that emits visible light when irradiated with light from the first light emitter described above, and a first phosphor (green / green yellow phosphor) to be described later is used. A second phosphor (a red phosphor, a blue phosphor, an orange phosphor, etc.), which will be described later, is contained as appropriate according to the application. Further, for example, the second light emitter is configured by dispersing the first and second phosphors in a sealing material.

The composition of the phosphor, there is no particular limitation on the other phosphors of the phosphor of the present invention to be contained as a green / green-yellow _{phosphor, Y 3 Al 5 O 12,} Sr 2 SiO 4 and the like is a crystalline matrix Metal oxides typified by, metal nitrides typified by Sr ₂ Si ₅ N ₈ , phosphates typified by Ca ₅ (PO ₄ ) ₃ Cl, etc. In sulfide, ions of rare earth metals such as Ce, Pr, Nd, Pm, Sm, Eu, Tb, Dy, Ho, Er, Tm, Yb, and ions of metals such as Ag, Cu, Au, Al, Mn, Sb Are preferably combined as an activator element or a coactivator element.

Preferred examples of the crystal matrix include sulfides such as (Zn, Cd) S, SrGa ₂ S ₄ , SrS, and ZnS; oxysulfides such as Y ₂ O ₂ S; (Y, Gd) ₃ Al ₅ O ₁₂ , YAlO ₃ , BaMgAl ₁₀ O ₁₇ , (Ba, Sr) (Mg, Mn) Al ₁₀ O ₁₇ , (Ba, Sr, Ca) (Mg, Zn, Mn) Al ₁₀ O ₁₇ , BaAl ₁₂ O ₁₉ , CeMgAl ₁₁ O ₁₉ , aluminate such as (Ba, Sr, Mg) O.Al ₂ O ₃ , BaAl ₂ Si ₂ O ₈ , SrAl ₂ O ₄ , Sr ₄ Al ₁₄ O ₂₅ , Y ₃ Al ₅ O ₁₂ ; Y ₂ SiO ₅ , silicates such as Zn ₂ SiO ₄ ; oxides such as SnO ₂ and Y ₂ O ₃ ; borate salts such as GdMgB ₅ O ₁₀ and (Y, Gd) BO ₃ ; Ca ₁₀ (PO ₄ ) ₆ (F, _{Cl) 2, (Sr, Ca} , Ba, Mg) 10 (PO 4) 6 halophosphate of ₂ such as _{Cl; Sr 2 P 2 O 7} , ( a, Ce) phosphate PO ₄ and the like; and the like.

However, the crystal matrix and the activator element or coactivator element are not particularly limited in element composition, and can be partially replaced with elements of the same family, and the obtained phosphor is light in the near ultraviolet to visible region. Any material that absorbs and emits visible light can be used.
Specifically, the following phosphors can be used, but these are merely examples, and phosphors that can be used in the present invention are not limited to these.

<2-2-1. First phosphor>
The second light emitter in the light emitting device of the present invention contains at least the above-described phosphor of the present invention as the first phosphor. Any one of the phosphors of the present invention may be used alone, or two or more thereof may be used in any combination and ratio. In addition to the phosphor of the present invention, a phosphor that emits fluorescence of the same color as the phosphor of the present invention (same color combined phosphor) may be used as the first phosphor. Usually, since the phosphor of the present invention is a green / green-yellow phosphor, another type of green phosphor can be used together with the phosphor of the present invention as the first phosphor.

As a 1st fluorescent substance, the green fluorescent substance which can be used together with the fluorescent substance of this invention is illustrated below. In addition, these may be used individually by 1 type and may use 2 or more types together by arbitrary combinations and ratios.
As the green phosphor other than the phosphor of the present invention, for example, it is composed of fractured particles having a fracture surface, and emits light in the green region (Ba, Ca, Sr, Mg) ₂ SiO ₄ : with europium represented by Eu. Examples include active alkaline earth silicate phosphors.

Other green phosphors include Eu-activated aluminate phosphors such as Sr ₄ Al ₁₄ O ₂₅ : Eu, (Ba, Sr, Ca) Al ₂ O ₄ : Eu; (Sr, Ba) Al _{2 Si 2 O 8: Eu, (} Ba, Mg) 2 SiO 4: Eu, (Ba, Sr, Ca, Mg) 2 SiO 4: Eu, (Ba, Sr, Ca) 2 (Mg, Zn) Si 2 O 7 : Eu, (Ba, Ca, Sr, Mg) ₉ (Sc, Y, Lu, Gd) ₂ (Si, Ge) ₆ O ₂₄ : Eu-activated silicate phosphor such as Eu; Y ₂ SiO ₅ : Ce, Ce, Tb activated silicate phosphors such as Tb; Sr ₂ P ₂ O ₇ —Sr ₂ B ₂ O ₅ : Eu activated borate phosphate phosphors such as Eu; Sr ₂ Si ₃ O ₈ -2SrCl ₂ : Eu-activated halo silicate phosphor such as Eu; Zn ₂ SiO _4: Mn-activated silicate phosphors such as _{Mn; CeMgAl 11 O 19: Tb} , ₃ Al ₅ O _12: Tb-activated aluminate phosphors such as _{Tb; Ca 2 Y 8 (SiO} 4) 6 O 2: Tb, La 3 Ga 5 SiO 14: Tb -activated silicate phosphors such as Tb; (Sr, Ba, Ca) Ga ₂ S ₄ : Eu, Tb, Sm activated thiogallate phosphors such as Eu, Tb, Sm, etc .; Y ₃ (Al, Ga) ₅ O ₁₂ : Ce, (Y, Ga, Tb, La, Sm, Pr, Lu) ₃ (Al, Ga) ₅ O ₁₂ : Ce-activated aluminate phosphor such as Ce; Ca ₃ Sc ₂ Si ₃ O ₁₂ : Ce, Ca ₃ (Sc, Mg, Na, Li) ₂ Si ₃ O ₁₂ : Ce-activated silicate phosphor such as Ce; CaSc ₂ O ₄ : Ce-activated oxide phosphor such as Ce; Eu-activated oxynitride phosphor such as Eu-activated β sialon _{; BaMgAl 10 O 17: Eu,} Eu such as Mn, Mn-activated aluminate phosphor; SrAl ₂ O _4: Eu such as Eu Activated aluminate phosphors; (La, Gd, Y) 2 O 2 S: Tb Tsukekatsusan sulfide phosphor such as Tb; LaPO _4: Ce, Ce and Tb such, Tb-activated phosphate phosphor; Sulfide phosphors such as ZnS: Cu, Al, ZnS: Cu, Au, Al; (Y, Ga, Lu, Sc, La) BO ₃ : Ce, Tb, Na ₂ Gd ₂ B ₂ O ₇ : Ce, Tb , (Ba, Sr) ₂ (Ca, Mg, Zn) B ₂ O ₆ : Ce, Tb-activated borate phosphor such as K, Ce, Tb; Ca ₈ Mg (SiO ₄ ) ₄ Cl ₂ : Eu, Mn Eu, Mn-activated halosilicate phosphors such as (Sr, Ca, Ba) (Al, Ga, In) ₂ S ₄ : Eu-activated thioaluminate phosphors and thiogallate phosphors such as Eu; Sr) ₈ (Mg, Zn) (SiO ₄ ) ₄ Cl ₂ : Eu, Mn activated halosilicate phosphor such as Eu, Mn; M ₃ S i ₆ O ₉ N ₄ : Eu, M ₂ Si ₇ O ₁₀ N ₄ : Eu (where M represents an alkaline earth metal element). It is also possible to use Eu-activated oxynitride phosphors such as

In addition, as the green phosphor, it is also possible to use a pyridine-phthalimide condensed derivative, a benzoxazinone-based, a quinazolinone-based, a coumarin-based, a quinophthalone-based, a nartaric imide-based fluorescent dye, or an organic phosphor such as a terbium complex. is there.
The emission peak wavelength λ _p (nm) of the first phosphor used in the light emitting device of the present invention is preferably in the range of usually 525 nm or more, particularly 530 nm or more, and usually 600 nm or less, especially 590 nm or less. If this emission peak wavelength λ _p is too short, the green color may become too strong, while if it is too long, it tends to be reddish, and the characteristics as green / green yellow light may be deteriorated in all cases.

Moreover, it is preferable that the relative intensity of the emission peak of the first phosphor used in the light emitting device of the present invention is higher.
The half-value width (FWHM) of the emission peak of the first phosphor used in the light emitting device of the present invention is usually 75 nm or more, particularly 80 nm or more, more preferably 82 nm or more, and usually 89 nm or less, especially 88 nm or less. Furthermore, it is preferable that it is the range of 86 nm or less. If the full width at half maximum FWHM is too narrow, the emission intensity may decrease, and if it is too wide, the color purity may decrease.

<2-2-2. Second phosphor>
The second light emitter in the light emitting device of the present invention may contain a phosphor (that is, a second phosphor) in addition to the first phosphor described above, depending on the application. The second phosphor is a phosphor having an emission wavelength different from that of the first phosphor. Usually, since these second phosphors are used to adjust the color tone of light emitted from the second light emitter, the second phosphor emits fluorescence having a color different from that of the first phosphor. Often phosphors are used. As described above, since a green / green-yellow phosphor is usually used as the first phosphor, examples of the second phosphor include a green / green phosphor such as a yellow phosphor, a blue phosphor, and an orange to red phosphor. A phosphor other than the green-yellow phosphor is used.

(Orange to red phosphor)
When an orange or red phosphor is used as the second phosphor, any orange or red phosphor can be used as long as the effects of the present invention are not significantly impaired. In this case, the emission peak wavelength of the orange to red phosphor is usually in the wavelength range of usually 580 nm or more, preferably 585 nm or more, and usually 780 nm or less, preferably 700 nm or less. Examples of such orange to red phosphors are europium composed of broken particles having a red fracture surface and emitting red region (Mg, Ca, Sr, Ba) ₂ Si ₅ N ₈ : Eu. The activated alkaline earth silicon nitride-based phosphor is composed of growing particles having a substantially spherical shape as a regular crystal growth shape, and emits light in the red region (Y, La, Gd, Lu) ₂ O ₂ S: Examples include europium-activated rare earth oxychalcogenide phosphors represented by Eu.

  Furthermore, the oxynitride and / or acid containing at least one element selected from the group consisting of Ti, Zr, Hf, Nb, Ta, W, and Mo described in JP-A No. 2004-300247 A phosphor containing a sulfide and containing an oxynitride having an alpha sialon structure in which a part or all of the Al element is substituted with a Ga element can also be used in this embodiment. These are phosphors containing oxynitride and / or oxysulfide.

Other red phosphors include Eu-activated oxysulfide phosphors such as (La, Y) ₂ O ₂ S: Eu; Y (V, P) O ₄ : Eu, Y ₂ O ₃ : Eu, etc. (Ba, Sr, Ca, Mg) ₂ SiO ₄ : Eu, Mn, (Ba, Mg) ₂ SiO ₄ : Eu, Mn activated silicate phosphor such as Eu, Mn; Eu-activated tungstate phosphors such as LiW ₂ O ₈ : Eu, LiW ₂ O ₈ : Eu, Sm, Eu ₂ W ₂ O ₉ , Eu ₂ W ₂ O ₉ : Nb, Eu ₂ W ₂ O ₉ : Sm Eu-activated sulfide phosphors such as (Ca, Sr) S: Eu; Eu-activated aluminate phosphors such as YAlO ₃ : Eu; LiY ₉ (SiO ₄ ) ₆ O ₂ : Eu, Ca ₂ Y _{8 (SiO 4) 6 O 2:} Eu, (Sr, Ba, Ca) 3 SiO 5: Eu, Sr 2 BaSiO 5: Eu -activated silicate phosphors such as Eu; ( _{, Gd) 3 Al 5 O 12} : Ce, (Tb, Gd) 3 Al 5 O 12: Ce -activated aluminate phosphor such as Ce; (Mg, Ca, Sr , Ba) 2-y / 2 Si 5 N _8-y O _y : Eu (0 ≦ y <4), (Mg, Ca, Sr, Ba) SiN ₂ : Eu, (Mg, Ca, Sr, Ba) _{1-x / 2} AlSiN _3-x O _x : Eu activated nitride phosphor such as Eu (0 ≦ x <1); (Mg, Ca, Sr, Ba) _{1-x / 2} AlSiN _3−x O _x : Ce (0 ≦ x <1) Ce activated nitride phosphor; (Sr, Ca, Ba, Mg) ₁₀ (PO ₄ ) ₆ Cl ₂ : Eu, Mn activated halophosphate phosphor such as Eu, Mn; Ba ₃ MgSi ₂ O ₈ : Eu , Mn, (Ba, Sr, Ca, Mg) ₃ (Zn, Mg) Si ₂ O ₈ : Eu, Mn activated silicate phosphors such as Eu and Mn; 3.5 MgO · 0.5MgF ₂ · GeO ₂ : Mn etc. Mn-activated germanate phosphor; Eu-activated oxynitride phosphor such as Eu-activated α-sialon; (Gd, Y, Lu, La) ₂ O ₃ : Eu, Bi-activated oxide such as Eu and Bi (Gd, Y, Lu, La) ₂ O ₂ S: Eu, Bi-activated oxysulfide phosphor such as Eu, Bi; (Gd, Y, Lu, La) VO ₄ : Eu, Bi, etc. Eu, Bi-activated vanadate phosphors; SrY ₂ S ₄ : Eu, Ce-activated sulfide phosphors such as Eu and Ce; CaLa ₂ S ₄ : Ce-activated sulfide phosphors such as Ce; (Ba, (Sr, Ca) MgP ₂ O ₇ : Eu, Mn, (Sr, Ca, Ba, Mg, Zn) ₂ P ₂ O ₇ : Eu, Mn-activated phosphate phosphor such as Eu, Mn; (Y, Lu ) ₂ WO _6: Eu, Eu such as Mo, Mo-activated tungstate phosphor; (Ba, Sr, Ca) x Si y Nz: Eu, Ce ( however , X, y, z are an integer of 1 or more. Eu, Ce activated nitride phosphors such as (Ca, Sr, Ba, Mg) ₁₀ (PO ₄ ) ₆ (F, Cl, Br, OH) ₂ : Eu, Mn activated halolin such as Eu, Mn ((Y, Lu, Gd, Tb) _1-xy Sc _x Ce _y ) ₂ (Ca, Mg) _1-r (Mg, Zn) _{2 + r} Si _{3 -q} Ge _q O _{12 + δ} It is also possible to use Ce-activated silicate phosphors such as

  Examples of red phosphors include β-diketonates, β-diketones, aromatic carboxylic acids, red organic phosphors composed of rare earth element ion complexes having an anion such as Bronsted acid as a ligand, and perylene pigments (for example, Dibenzo {[f, f ′]-4,4 ′, 7,7′-tetraphenyl} diindeno [1,2,3-cd: 1 ′, 2 ′, 3′-lm] perylene), anthraquinone pigment, Lake pigments, azo pigments, quinacridone pigments, anthracene pigments, isoindoline pigments, isoindolinone pigments, phthalocyanine pigments, triphenylmethane basic dyes, indanthrone pigments, indophenol pigments, It is also possible to use a cyanine pigment or a dioxazine pigment.

Of the red phosphors, those having a peak wavelength in the range of 580 nm or more, preferably 590 nm or more, and 620 nm or less, preferably 610 nm or less can be suitably used as the orange phosphor. Examples of such orange phosphors include Eu-activated silicate phosphors such as (Sr, Ba, Ca) ₃ SiO ₅ : Eu, Sr ₂ BaSiO ₅ : Eu; (Sr, Mg) ₃ (PO ₄ ) ₂ : Sn-activated phosphate phosphor such as Sn ²⁺ ;

Any one of the red phosphors exemplified above may be used alone, or two or more may be used in any combination and ratio.
Among the above examples, as the red phosphor, (Ca, Sr, Ba) _{1-x / 2} AlSiN _3-x O _x : Eu (0 ≦ x <1), (Ca, Sr, Ba) _{1-x / 2} AlSiN _3-x O _x : Ce (0 ≦ x <1), (La, Y) ₂ O ₂ S: Eu is preferred, (Sr, Ca) _{1-x / 2} AlSiN _3-x O _x : Eu (0 ≦ x <1) and (La, Y) ₂ O ₂ S: Eu are particularly preferable.

Of the above examples, (Sr, Ba) ₃ SiO ₅ : Eu is preferable as the orange phosphor.
(Blue phosphor)
When a blue phosphor is used as the second phosphor, any blue phosphor can be used as long as the effects of the present invention are not significantly impaired. At this time, the emission peak wavelength of the blue phosphor is usually in the wavelength range of 420 nm or more, preferably 430 nm or more, more preferably 440 nm or more, and usually 490 nm or less, preferably 470 nm or less, more preferably 460 nm or less. Is preferred.

As such a blue phosphor, a europium-activated barium magnesium aluminate system represented by BaMgAl ₁₀ O ₁₇ : Eu composed of growing particles having a substantially hexagonal shape as a regular crystal growth shape and emitting light in a blue region. Europium activated halo represented by (Ca, Sr, Ba) ₅ (PO ₄ ) ₃ Cl: Eu, which is composed of phosphors and growing particles having a substantially spherical shape as a regular crystal growth shape, and emits light in the blue region. Calcium phosphate-based phosphor, composed of growing particles having an approximately cubic shape as a regular crystal growth shape, emits light in the blue region, and is activated by europium represented by (Ca, Sr, Ba) ₂ B ₅ O ₉ Cl: Eu It is composed of alkaline earth chloroborate phosphors and fractured particles having fractured surfaces, and emits light in the blue-green region (S _{, Ca, Ba) Al 2 O} 4: Eu or _{(Sr, Ca, Ba) 4} Al 14 O 25: activated alkaline earth with europium aluminate-based phosphor such as represented by Eu and the like.

Other blue phosphors include Sn-activated phosphate phosphors such as Sr ₂ P ₂ O ₇ : Sn; (Sr, Ca, Ba) Al ₂ O ₄ : Eu, (Sr, Ca, Ba) Eu activated aluminate phosphors such as ₄ Al ₁₄ O ₂₅ : Eu, BaMgAl ₁₀ O ₁₇ : Eu, BaAl ₈ O ₁₃ : Eu; Ce activated such as SrGa ₂ S ₄ : Ce, CaGa ₂ S ₄ : Ce Thiogallate phosphors; (Ba, Sr, Ca) MgAl ₁₀ O ₁₇ : Eu, BaMgAl ₁₀ O ₁₇ : Eu-activated aluminate phosphors such as Eu, Tb, Sm; (Ba, Sr, Ca) MgAl ₁₀ O ₁₇ : Eu, Mn activated aluminate phosphor such as Eu, Mn; (Sr, Ca, Ba, Mg) ₁₀ (PO ₄ ) ₆ Cl ₂ : Eu, (Ba, Sr, Ca) ₅ (PO ₄ ) ₃ (Cl, F, Br, OH): Eu-activated halophosphoric acid such as Eu, Mn, Sb _{Phosphor; BaAl 2 Si 2 O 8:} Eu, (Sr, Ba) 3 MgSi 2 O 8: Eu -activated silicate phosphors such as _{Eu; Sr 2 P 2 O 7} : Eu -activated phosphate such as Eu Phosphors; sulfide phosphors such as ZnS: Ag, ZnS: Ag, Al; Ce-activated silicate phosphors such as Y ₂ SiO ₅ : Ce; tungstate phosphors such as CaWO ₄ ; (Ba, Sr, _{Ca) BPO 5: Eu, Mn} , (Sr, Ca) 10 (PO 4) 6 · nB 2 O 3: Eu, 2SrO · 0.84P 2 O 5 · 0.16B 2 O 3: Eu such as Eu, Mn An activated borate phosphate phosphor; Eu-activated halosilicate phosphor such as Sr ₂ Si ₃ O ₈ .2SrCl ₂ : Eu;

Further, as the blue phosphor, for example, naphthalic acid imide-based, benzoxazole-based, styryl-based, coumarin-based, pyrazoline-based, triazole-based fluorescent dyes, organic phosphors such as thulium complexes, and the like can be used. .
Among the above examples, as the blue phosphor, BaMgAl ₁₀ O ₁₇ : Eu, (Ba, Ca, Mg) ₂ SiO ₄ : Eu, (Sr, Ca, Ba, Mg) ₁₀ (PO ₄ ) ₆ Cl ₂ : Eu is preferred, and BaMgAl ₁₀ O ₁₇ : Eu is particularly preferred.

(Yellow phosphor)
When a yellow phosphor is used as the second phosphor, any blue phosphor can be used as long as the effects of the present invention are not significantly impaired. At this time, the emission peak wavelength of the yellow phosphor is usually in the wavelength range of 530 nm or more, preferably 540 nm or more, more preferably 550 nm or more, and usually 620 nm or less, preferably 600 nm or less, more preferably 580 nm or less. Is preferred.

Examples of such yellow phosphors include various oxide-based, nitride-based, oxynitride-based, sulfide-based, and oxysulfide-based phosphors.
In particular, RE ₃ M ₅ O ₁₂ : Ce (where RE represents at least one element selected from the group consisting of Y, Tb, Gd, Lu, and Sm, and M represents Al, Ga, and Sc. And M ^a ₃ M ^b ₂ M ^c ₃ O ₁₂ : Ce (where M ^a is a divalent metal element and M ^b is a trivalent metal element) , M ^c represents a tetravalent metal element.) Garnet-based phosphor having a garnet structure represented by AE ₂ M ^d O ₄ : Eu (where AE is Ba, Sr, Ca, Mg, and And at least one element selected from the group consisting of Zn, and M ^d represents Si and / or Ge.), Etc., and oxygen of constituent elements of the phosphors of these systems oxynitride-based phosphor obtained by substituting a part of nitrogen of, AE _{1-x / 2 lSiN 3-x O x: Ce} (0 ≦ x <1) (. , where, AE represents Ba, Sr, Ca, and at least one element selected from the group consisting of Mg and Zn) Ca ₁ such Examples include phosphors activated with Ce, such as nitride-based phosphors having a _{-x / 2} AlSiN _3-x O _x (0 ≦ x <1) structure.

Other examples of yellow phosphors include sulfide-based fluorescence such as CaGa ₂ S ₄ : Eu, (Ca, Sr) Ga ₂ S ₄ : Eu, (Ca, Sr) (Ga, Al) ₂ S ₄ : Eu. Body: Ca _x (Si, Al) ₁₂ (O, N) ₁₆ : Oxynitride phosphor having SiAlON structure such as Eu (0 ≦ x <1); Eu-activated phosphor such as Eu Is also possible.
Examples of yellow phosphors include brilliant sulfoflavine FF (Color Index Number 56205), basic yellow HG (Color Index Number 46040), eosine (Color Index Number 45e 380a) Etc. can also be used.

  In addition, as a 2nd fluorescent substance, 1 type of fluorescent substance may be used independently, and 2 or more types of fluorescent substance may be used together by arbitrary combinations and a ratio. Further, the ratio between the first phosphor and the second phosphor is also arbitrary as long as the effects of the present invention are not significantly impaired. Therefore, the usage amount of the second phosphor, the combination of phosphors used as the second phosphor, and the ratio thereof may be arbitrarily set according to the use of the light emitting device.

<2-2-3. Physical properties of second phosphor>
The weight median diameter of the second phosphor used in the light emitting device of the present invention is usually in the range of 10 μm or more, especially 15 μm or more, and usually 30 μm or less, especially 20 μm or less. When the weight median diameter is too small, the luminance is lowered and the phosphor particles tend to aggregate. On the other hand, if the weight median diameter is too large, there is a tendency for coating unevenness and blockage of a dispenser or the like to occur.

<2-2-4. Selection of second phosphor>
In the light emitting device of the present invention, the presence / absence and type of the second phosphor (red phosphor, blue phosphor, orange phosphor, etc.) described above may be appropriately selected according to the use of the light emitting device. . For example, when the light-emitting device of the present invention is configured as a green / green-yellow light-emitting device, only the first phosphor (green / green-yellow phosphor) may be used, and the second phosphor is usually used. Is unnecessary.

On the other hand, when the light-emitting device of the present invention is configured as a light-emitting device that emits white light, a first light-emitting body, a first phosphor (green / green-yellow phosphor), and a white light-emitting device are obtained. What is necessary is just to combine a 2nd fluorescent substance appropriately. Specifically, examples of preferable combinations of the first light emitter, the first phosphor, and the second phosphor in the case where the light emitting device of the present invention is configured as a white light emitting device include the following: (I) to (iii) are included.
(I) A blue light emitter (such as a blue LED) is used as the first light emitter, a green / green yellow phosphor (such as the phosphor of the present invention) is used as the first phosphor, and a second phosphor is used. A red phosphor (preferably having an emission peak wavelength of 570 nm or more and 680 nm or less) is used. In this case, red phosphors include (Sr, Ca) _{1-x / 2} AlSiN _3-x O _x : Eu (0 ≦ x <1) and (Mg, Ca, Sr, Ba) _{2-y / 2} Si. _One or two or more red phosphors selected from the group consisting of ₅ N _8-y O _y : Eu (0 ≦ y ≦ 4) are preferred. Among these, it is preferable to use a combination of a blue LED, the phosphor of the present invention, and Ca _{1-x / 2} AlSiN _3-x O _x : Eu (0 ≦ x <1) as a red phosphor.
(Ii) A near ultraviolet light emitter (near ultraviolet LED or the like) is used as the first light emitter, a green / green yellow phosphor (such as the phosphor of the present invention) is used as the first phosphor, and the second fluorescence. A blue phosphor and a red phosphor (preferably those having an emission peak wavelength of 570 nm or more and 680 nm or less) are used in combination. In this case, BaMgAl ₁₀ O ₁₇ : Eu is preferable as the blue phosphor. As red phosphors, (Sr, Ca) _{1-x / 2} AlSiN _3-x O _x : Eu (0 ≦ x <1), (Mg, Ca, Sr, Ba) _{2-y / 2} Si ₅ One or two or more red phosphors selected from the group consisting of N _8-y O _y : Eu (0 ≦ y ≦ 4) and La ₂ O ₂ S: Eu are preferable. Among them, a near-ultraviolet LED, the phosphor of the present invention, BaMgAl ₁₀ O ₁₇ : Eu as a blue phosphor, and Ca _{1-x / 2} AlSiN _3-x O _x : Eu (0 ≦ x <1) as a red phosphor. ) And / or La ₂ O ₂ S: Eu is preferably used in combination.
(Iii) A blue light emitter (blue LED or the like) is used as the first light emitter, a green / green yellow phosphor (the phosphor of the present invention) is used as the first phosphor, and the second phosphor is used. An orange phosphor (preferably having an emission peak wavelength of 580 nm or more and 620 nm or less) is used. In this case, (Sr, Ba) ₃ SiO ₅ : Eu is preferable as the orange phosphor.

  In addition, the phosphor of the present invention is mixed with other phosphors (here, mixing does not necessarily mean that the phosphors need to be mixed with each other, but means that different types of phosphors are combined). ) Can be used. In particular, when phosphors are mixed in the combination described above, a preferable phosphor mixture is obtained. In addition, there is no restriction | limiting in particular in the kind of fluorescent substance to mix, and its ratio.

<2-2-5. Sealing material>
The second light emitter is configured, for example, by dispersing the above-described first phosphor and the second phosphor used as necessary in a sealing material.
Examples of the sealing material include thermoplastic resins, thermosetting resins, and photocurable resins. Specifically, methacrylic resin such as methyl polymethacrylate; styrene resin such as polystyrene and styrene-acrylonitrile copolymer; polycarbonate resin; polyester resin; phenoxy resin; butyral resin; polyvinyl alcohol; ethyl cellulose, cellulose acetate, cellulose Cellulose resins such as acetate butyrate; epoxy resins; phenol resins; silicone resins and the like. Further, an inorganic material such as a siloxane bond formed by solidifying a solution obtained by hydrolyzing a solution containing an inorganic material such as a metal alkoxide, a ceramic precursor polymer or a metal alkoxide by a sol-gel method, or a combination thereof. An inorganic material can be used.

Of these, from the viewpoint of heat resistance, ultraviolet resistance (UV) resistance, etc., a solution obtained by hydrolyzing a solution containing a silicone resin, a metal alkoxide, a ceramic precursor polymer or a metal alkoxide by a sol-gel method, or these An inorganic material obtained by solidifying these combinations, for example, an inorganic material having a siloxane bond is preferable.
Among these, when used with the phosphor of the present invention, it is preferable to use a silicone resin or a silicone-based material, and it is more preferable to use a silicone resin.

Examples of the silicone resin include addition reaction type silicone resins and condensation reaction type silicone resins. Among these, condensation reaction type silicone resins containing a phenyl group are preferable. Further, it is more preferable that the silicone resin or the silicone-based material has a refractive index of 1.45 or more.
Moreover, among such sealing materials, a silicone material and a silicone resin having one or more of the following features <1> to <3> are particularly preferable.
<1> The solid Si-nuclear magnetic resonance (NMR) spectrum has at least one of the following peaks (a) and / or (b).

(A) A peak whose peak top is in the region of chemical shift −40 ppm or more and 0 ppm or less, and whose peak half-value width is 0.3 ppm or more and 3.0 ppm or less.
(B) A peak whose peak top position is in a region where the chemical shift is −80 ppm or more and less than −40 ppm, and the half width of the peak is 0.3 ppm or more and 5.0 ppm or less.
<2> The silicon content is 20% by weight or more.
<3> The silanol content is 0.1% by weight or more and 10% by weight or less.

In the present invention, among the above features <1> to <3>, a silicone material or a silicone resin having the feature <2> is preferable. More preferably, a silicone material or a silicone resin having the above characteristics <1> and <2> is preferable. Particularly preferably, a silicone material or a silicone resin having all of the above characteristics <1> to <3> is preferable.
Hereinafter, these features <1> to <3> will be described. Hereinafter, the silicone material having the above characteristics <1> to <3> is referred to as “silicone material used in the present invention”.

(Solid Si-NMR spectrum)
The compound containing silicon as a main component is represented by the SiO ₂ .nH ₂ O formula, but structurally, oxygen atoms O are bonded to the vertices of the tetrahedron of silicon atoms Si, and these oxygen atoms It has a structure in which silicon atoms Si are further bonded to O and spread in a net shape. The schematic diagram shown below represents the Si—O net structure while ignoring the tetrahedral structure, and in the repeating unit of Si—O—Si—O—, one oxygen atom O is represented. Some are substituted with other members (for example, —H, —CH _3, etc.), and when attention is paid to one silicon atom Si, as shown in (A) of the schematic diagram, four —OSi are silicon atoms having Si (Q ^4), a silicon atom Si (Q ³⁾ having three -OSi as shown in the schematic diagram (B) or the like is present. Then, in the solid-state Si-NMR measurement, peaks based on each silicon atom Si above is sequentially referred to Q ⁴ peak, Q ³ peak, and ....

These silicon atoms having four bonded oxygen atoms are generally referred to as Q sites. In the present invention, Q ^{0 to} Q ⁴ peaks derived from the Q site are referred to as a Q ⁿ peak group. The Q ⁿ peak group of the silica film containing no organic substituent is usually observed as a multimodal peak continuous in the region of chemical shift of −80 ppm to −130 ppm.
In contrast, silicon atoms to which three oxygen atoms are bonded and other atoms (usually carbon) are bonded are generally referred to as T sites. The peak derived from the T site is observed as each peak of T ^{0 to} T ³ as in the case of the Q site. In the present invention, each peak derived from the T site is referred to as a T ⁿ peak group. The T ⁿ peak group is generally observed as a multimodal peak continuous in the region on the higher magnetic field side (usually chemical shift of −80 ppm to −40 ppm) than the Q ⁿ peak group.

Furthermore, a silicon atom to which two oxygen atoms are bonded and other atoms (usually carbon) are bonded is generally referred to as a D site. Similarly to the peak group derived from the Q site and the T site, the peak derived from the D site is also observed as each peak of D ^{0 to} D ⁿ (referred to as a D ⁿ peak group), and the peaks of Q ⁿ and T ⁿ are observed. Furthermore, it is observed as a multimodal peak in a region on the high magnetic field side (normally, a region with a chemical shift of 0 ppm to −40 ppm). The ratio of the area of each peak group of D ⁿ , T ⁿ , and Q ⁿ is equal to the molar ratio of silicon atoms placed in the environment corresponding to each peak group. In terms of the molar amount, the total area of the D ⁿ peak group and the T ⁿ peak group usually corresponds to the molar amount of all silicon directly bonded to the carbon atom.

Bond When measuring the solid Si-NMR spectrum of a silicone-based material used in the present invention, the D ⁿ peak group and T ⁿ peak group originating from silicon atoms in which carbon atoms directly bonded organic group, and the carbon atom of an organic group ^Qn peaks derived from silicon atoms not appearing in different regions. Among these peaks, the peak of less than −80 ppm corresponds to the Q ⁿ peak as described above, and the peaks of −80 ppm or more correspond to the D ⁿ and T ⁿ peaks. In the silicone material of the present invention, the Q ⁿ peak is not essential, but at least one, preferably a plurality of peaks are observed in the D ⁿ and T ⁿ peak regions.

In the silicone material used in the present invention, the half width of the peak observed in the region of −80 ppm or more is smaller (narrower) than the half width range of the silicone material known so far by the sol-gel method. It is characterized by that.
When organized by chemical shift, in the silicone-based material used in the present invention, the half width of the T ⁿ peak group observed at a peak top position of −80 ppm or more and less than −40 ppm is usually 5.0 ppm or less, preferably 4 0.0 ppm or less, and usually 0.3 ppm or more, preferably 0.4 ppm or more.

Similarly, the full width at half maximum of the D ⁿ peak group observed at the peak top position of −40 ppm or more and 0 ppm or less is generally smaller than that of the T ⁿ peak group due to the small restraint of molecular motion, and usually 3.0 ppm or less. , Preferably 2.0 ppm or less, and usually in the range of 0.3 ppm or more.
When the half-value width of the peak observed in the chemical shift region is larger than the above range, the molecular motion is constrained and the strain is large, the crack is likely to occur, and the member is inferior in heat resistance and weather resistance. There is. For example, in the case where a large amount of tetrafunctional silane is used, or in the state where rapid drying is performed in the drying process and a large internal stress is stored, the full width at half maximum is larger than the above range.

In addition, when the half width of the peak is smaller than the above range, Si atoms in the environment are not involved in the siloxane crosslinking, and the trifunctional silane remains in an uncrosslinked state and is formed mainly of siloxane bonds. It may be a member that is inferior in heat resistance and weather resistance to a substance.
The composition of the silicone material used in the present invention is limited to the case where the crosslinking in the system is mainly formed by inorganic components including silica. That is, even in the case of a silicone material containing a small amount of Si component in a large amount of organic component, even if the peak in the above-mentioned half-value range is observed at -80 ppm or more, good heat resistance / light resistance and coating performance cannot be obtained. .

The value of the chemical shift of the silicone material used in the present invention can be calculated based on the results of solid Si-NMR measurement using the following method, for example. In addition, analysis of measurement data (half-width or silanol amount analysis) is performed by a method of dividing and extracting each peak by, for example, waveform separation analysis using a Gaussian function or a Lorentz function.
{Solid Si-NMR spectrum measurement and silanol content calculation}
When performing a solid Si-NMR spectrum about a silicone type material, a solid Si-NMR spectrum measurement and waveform separation analysis are performed on condition of the following. Further, from the obtained waveform data, the half width of each peak is determined for the silicone material. Also, from the ratio of the peak area derived from silanol to the total peak area, the ratio (%) of silicon atoms that are silanols in all silicon atoms is obtained, and the silanol content is determined by comparing with the silicon content analyzed separately. Ask.

{Device conditions}
Apparatus: Chemmagnetics Infinity CMX-400 Nuclear magnetic resonance spectrometer
²⁹ Si resonance frequency: 79.436 MHz
Probe: 7.5 mmφ CP / MAS probe Measurement temperature: room temperature Sample rotation speed: 4 kHz
Measurement method: Single pulse method
¹ H decoupling frequency: 50 kHz
²⁹ Si flip angle: 90 °
²⁹ Si 90 ° pulse width: 5.0μs
Repeat time: 600s
Integration count: 128 Observation width: 30 kHz
Broadening factor: 20Hz
{Data processing method}
For silicone-based materials, 512 points are taken as measurement data, zero-filled to 8192 points, and Fourier transformed.

{Waveform separation analysis method}
For each peak of the spectrum after Fourier transform, optimization calculation is performed by a non-linear least square method with the center position, height, and half width of the peak shape created by Lorentz waveform and Gaussian waveform or a mixture of both as variable parameters.
For peak identification, refer to AIChE Journal, 44 (5), p.1141, 1998, etc.

(Silicon content)
The silicone material used in the present invention has a silicon content of 20% by weight or more (feature <2>).
The basic skeleton of a conventional silicone material is an organic resin such as an epoxy resin having a carbon-carbon and carbon-oxygen bond as the basic skeleton, whereas the basic skeleton of the silicone material of the present invention is glass (silicate). It is the same inorganic siloxane bond as glass). As is apparent from the chemical bond comparison table shown in Table 1 below, this siloxane bond has the following characteristics excellent as a silicone material.
(I) Since the binding energy is large and thermal decomposition and photolysis are difficult, light resistance is good.
(II) It is slightly polarized electrically.
(III) The degree of freedom of the chain structure is large, a structure having a high flexibility is possible, and the chain structure can freely rotate about the siloxane chain center.
(IV) The degree of oxidation is large and no further oxidation occurs.
(V) Excellent electrical insulation.

  Because of these characteristics, silicone-based silicone materials that are formed with a skeleton in which siloxane bonds are three-dimensionally bonded with a high degree of crosslinking are close to inorganic materials such as glass or rock, and have a high heat resistance and light resistance. Can be understood. In particular, a silicone-based material having a methyl group as a substituent has no absorption in the ultraviolet region, so that photolysis hardly occurs and has excellent light resistance.

As described above, the silicon content of the silicone-based material used in the present invention is 20% by weight or more, preferably 25% by weight or more, and more preferably 30% by weight or more. On the other hand, the upper limit is usually in the range of 47% by weight or less because the silicon content of the glass composed solely of SiO ₂ is 47% by weight.
Note that the silicon content of the silicone-based material is calculated based on the results obtained by performing inductively coupled plasma spectroscopy (hereinafter abbreviated as “ICP” as appropriate), for example, using the following method. be able to.

{Measurement of silicon content}
A single cured material of silicone material is pulverized to about 100 μm, and baked in a platinum crucible in the air at 450 ° C. for 1 hour, then 750 ° C. for 1 hour, and 950 ° C. for 1.5 hours. After removing the residue, add 10 times or more amount of sodium carbonate to a small amount of the resulting residue, heat with a burner to melt, cool this, add demineralized water, and further adjust the pH to neutral with hydrochloric acid. The volume is adjusted to about several ppm as silicon, and ICP analysis is performed.

(Silanol content)
The silicone material used in the present invention has a silanol content of usually 0.1% by weight or more, preferably 0.3% by weight or more, and usually 10% by weight or less, preferably 8% by weight or less, more preferably The range is 5% by weight or less (feature <3>). Since the silicone material used in the present invention has a low silanol content, there is little change over time, excellent long-term performance stability, and excellent performance with low moisture absorption and moisture permeability. However, since a member containing no silanol is inferior in adhesion, there exists an optimum range for the silanol content as described above.

  In addition, the silanol content rate of a silicone type material performs solid Si-NMR spectrum measurement, for example using the method demonstrated in (Solid Si-NMR spectrum measurement and calculation of silanol content rate) of (Solid Si-NMR spectrum), From the ratio of the peak area derived from silanol to the total peak area, the ratio (%) of silicon atoms that are silanols in all silicon atoms can be obtained and compared with the silicon content analyzed separately.

In addition, since the silicone material used in the present invention contains an appropriate amount of silanol, the silanol hydrogen bonds to the polar portion present on the device surface, thereby exhibiting adhesion. Examples of the polar part include a hydroxyl group and a metalloxane-bonded oxygen.
In addition, the silicone material used in the present invention forms a covalent bond by dehydration condensation with the hydroxyl group on the device surface by heating in the presence of an appropriate catalyst, and develops stronger adhesion. Can do.

On the other hand, if there is too much silanol, the inside of the system will thicken and it will be difficult to apply, or it will become more active and solidify before the light-boiling components volatilize by heating, leading to increased foaming and internal stress. It may occur and induce cracks.
(Measured hardness value)
The silicone material used in the present invention preferably exhibits an elastomeric shape. Specifically, the hardness measurement value (Shore A) by durometer type A is usually 5 or more, preferably 7 or more, more preferably 10 or more, and usually 90 or less, preferably 80 or less, more preferably 70 or less. Yes (feature <4>). By having a hardness measurement value in the above range, it is possible to obtain an advantage that cracks hardly occur and that reflow resistance and temperature cycle resistance are excellent.

  The hardness measured value (Shore A) can be measured by the method described in JIS K6253. Specifically, the measurement can be performed using an A-type rubber hardness meter manufactured by Furusato Seiki Seisakusho. In addition, reflow refers to a soldering method in which a solder paste is printed on a substrate, a component is mounted thereon, and heated and joined. The reflow resistance refers to a property that can withstand a thermal shock of a maximum temperature of 260 ° C. for 10 seconds.

(Other additives)
In the silicone material used in the present invention, in order to adjust the refractive index of the sealing member, a metal element capable of providing a metal oxide having a high refractive index can be present in the sealing member. Examples of metal elements that give a metal oxide having a high refractive index include Si, Al, Zr, Ti, Y, Nb, and B. These metal elements may be used alone or in combination of two or more in any combination and ratio.

  The presence form of such a metal element is not particularly limited as long as the transparency of the sealing member is not impaired. For example, even if a uniform glass layer is formed as a metalloxane bond, the metal element is present in a particulate form in the sealing member. It may be. When present in the form of particles, the structure inside the particles may be either amorphous or crystalline, but is preferably a crystalline structure in order to provide a high refractive index. Further, the particle diameter is usually not more than the emission wavelength of the semiconductor light emitting device, preferably not more than 100 nm, more preferably not more than 50 nm, particularly preferably not more than 30 nm so as not to impair the transparency of the sealing member. For example, by mixing particles of silicon oxide, aluminum oxide, zirconium oxide, titanium oxide, yttrium oxide, niobium oxide, etc. with a silicone-based material, the metal element can be present in the sealing member in the form of particles. .

The silicone material used in the present invention may further contain known additives such as a diffusing agent, a filler, a viscosity modifier, and an ultraviolet absorber.
Specific examples of the silicone material used in the present invention include the silicone materials described in Japanese Patent Application No. 2006-176468.
[2-3. Configuration of light emitting device
The light-emitting device of the present invention is not particularly limited as long as it includes the first light-emitting body and the second light-emitting body described above, but usually the first light-emitting body described above on an appropriate frame. And a second light emitter. At this time, the second light emitter is excited by the light emission of the first light emitter (that is, the first and second phosphors are excited) to emit light, and the first light emitter emits light. And / or it arrange | positions so that light emission of a 2nd light-emitting body may be taken out outside. In this case, the first phosphor and the second phosphor are not necessarily mixed in the same layer. For example, the second phosphor is contained on the layer containing the first phosphor. For example, the phosphor may be contained in a separate layer for each color development of the phosphor, such as by laminating layers.

  In the light emitting device of the present invention, members other than the first light emitter, the second light emitter, and the frame described above may be used. For example, <2-2-5. Examples thereof include the sealing materials described in “Sealing Material>. As a specific example, the sealing material is used for the purpose of dispersing the second light emitter in the light emitting device, or for the purpose of bonding the first light emitter, the second light emitter and the frame. be able to.

  As the sealing material, for example, <2-2-5. The same materials as those exemplified as the constituent material of the second light emitter in the sealing material> can be used. Other examples of the sealing resin used usually include thermoplastic resins, thermosetting resins, and photocurable resins. Specifically, for example, methacrylic resin such as polymethylmethacrylate; styrene resin such as polystyrene and styrene-acrylonitrile copolymer; polycarbonate resin; polyester resin; phenoxy resin; butyral resin; polyvinyl alcohol; Cellulose resins such as cellulose acetate butyrate; epoxy resins; phenol resins; silicone resins. Further, an inorganic material such as a siloxane bond formed by solidifying a solution obtained by hydrolyzing a solution containing an inorganic material such as a metal alkoxide, a ceramic precursor polymer or a metal alkoxide by a sol-gel method, or a combination thereof. An inorganic material can be used.

[2-4. Embodiment of Light Emitting Device]
Hereinafter, the light-emitting device of the present invention will be described in more detail with reference to specific embodiments. However, the present invention is not limited to the following embodiments, and does not depart from the gist of the present invention. It can be implemented with arbitrary modifications.
FIG. 1 is a diagram schematically showing a configuration of a light emitting device according to an embodiment of the present invention. The light emitting device 1 of the present embodiment absorbs a part of light emitted from the frame 2, a blue LED (first light emitter) 3 that is a light source, and the blue LED 3, and emits light having a wavelength different from that. It comprises a phosphor-containing part (second light emitter) 4.

  The frame 2 is a metal base for holding the blue LED 3 and the phosphor-containing portion 4. On the upper surface of the frame 2, a trapezoidal concave section (dent) 2A having an opening on the upper side in FIG. Thereby, since the frame 2 has a cup shape, the light emitted from the light emitting device 1 can have directivity, and the emitted light can be used effectively.

  A blue LED 3 is installed as a light source at the bottom of the recess 2 </ b> A of the frame 2. The blue LED 3 is an LED that emits blue light when supplied with electric power. Part of the blue light emitted from the blue LED 3 is absorbed as excitation light by the light-emitting substance (the first phosphor and the second phosphor) in the phosphor-containing part 4, and another part is The light is emitted from the light emitting device 1 in a predetermined direction.

In addition, the blue LED 3 is installed at the bottom of the recess 2A of the frame 2 as described above. Here, the frame 2 and the blue LED 3 are bonded to each other by the adhesive 5, so that the blue LED 3 is attached to the frame 2. is set up.
Further, a gold wire 6 for supplying power to the blue LED 3 is attached to the frame 2. That is, an electrode (not shown) provided on the upper surface of the blue LED 3 is connected by wire bonding using the wire 6, and power is supplied to the blue LED 3 by energizing the wire 6. The blue LED 3 emits blue light. One or a plurality of wires 6 are attached in accordance with the structure of the blue LED 3.

  Further, the concave portion 2A of the frame 2 is provided with a phosphor-containing portion 4 that absorbs part of the light emitted from the blue LED 3 and emits light having a different wavelength. The phosphor-containing part 4 is formed of a phosphor and a transparent resin (sealing material). The phosphor is a substance that is excited by blue light emitted from the blue LED 3 and emits light having a wavelength longer than that of the blue light. The phosphor constituting the phosphor-containing portion 4 may be a single type or a mixture of a plurality of colors, and the sum of the light emitted from the blue LED 3 and the light emitted from the phosphor light-emitting portion 4 is a desired color. Choose to be. The color is not limited to white, but may be yellow, orange, pink, purple, blue-green, or the like. Further, it may be an intermediate color between these colors and white. Here, for example, a green / green yellow phosphor (first phosphor) and a red phosphor (second phosphor) made of the phosphor of the present invention are used as phosphors, and white light is emitted from the light emitting device. It is supposed to be able to.

The mold unit 7 functions as a lens for protecting the blue LED 3, the phosphor-containing unit 4, the wire 6 and the like from the outside and controlling the light distribution characteristics. For example, an epoxy resin can be used for the mold portion 7.
Since the light emitting device of the present embodiment is configured as described above, when the blue LED 3 emits light, the green phosphor and the red phosphor in the phosphor light emitting section 4 are excited to emit light. Thus, the light emitting device emits white light composed of blue light emitted from the blue LED 3, green / green yellow light emitted from the green / green yellow phosphor, and red light emitted from the red phosphor.

At this time, the light emitting device of the present invention is characterized by its high NTSC ratio. Specifically, the NTSC ratio of the light emitting device of the present invention is usually 70 or more, preferably 75 or more. A high NTSC ratio indicates that the range of colors that can be displayed when used as a display backlight is wide.
In addition, the measuring method of NTSC ratio is as follows.

In the NTSC system, which is the standard of Japanese color TV, the standard R, G, B chromaticity points are defined as follows by the point (x, y) on the CIE chromaticity coordinates.
R (0.67, 0.33), G (0.21, 0.71), B (0.14, 0.08)
When the area of a triangle formed by three points of RGB is 100, the area of the triangle formed by R, G, and B of the display to be obtained, specifically, the monochrome RGB is expressed on the display to be obtained and the chromaticity ( x, y) is measured, and a value obtained by dividing the area of the triangle obtained by plotting on the CIE chromaticity diagram by the area of the standard triangle of NTSC is defined as NTSC ratio (%).

The light-emitting device of the present invention is not limited to the above-described embodiment, and can be implemented with any changes without departing from the gist thereof.
For example, a surface-emitting type can be used as the first light emitter, and a film-like one can be used as the second light emitter. In this case, it is preferable to have a shape in which the film-shaped second light emitter is in direct contact with the light emitting surface of the first light emitter. In addition, contact here means producing the state which the 1st light-emitting body and the 2nd light-emitting body have touched exactly without passing air or gas. As a result, it is possible to avoid a light amount loss in which light from the first light emitter is reflected by the film surface of the second light emitter and oozes out, so that the light emission efficiency of the entire apparatus can be improved.

  FIG. 2 is a schematic perspective view showing an example of a light emitting device in which a surface light emitting type is used as the first light emitter and a film-like one is applied as the second light emitter. In the light-emitting device 8 shown in FIG. 2, a surface-emitting GaN-based LD 10 as a first light-emitting body is provided on a substrate 9, and a film-shaped second light-emitting body 11 is formed on the surface-emitting GaN-based LD 10. Has been. Here, in order to create a state where they are in contact with each other, the LD 10 as the first light emitter and the second light emitter 11 are prepared separately, and their surfaces are brought into contact with each other by an adhesive or other means. Alternatively, the second light emitter 11 may be formed (molded) on the light emitting surface of the LD 10. As a result, the LD 11 and the second light emitter 11 can be brought into contact with each other.

According to the light-emitting device 8 having such a configuration, in addition to the same advantages as those of the above-described embodiment, it is possible to improve the light emission efficiency by avoiding the loss of light amount.
[2-5. Application of light emitting device)
The application of the light-emitting device of the present invention is not particularly limited, and can be used in various fields in which ordinary light-emitting devices are used. However, since the color reproduction range is wide and color rendering is high, the image It is particularly preferably used as a light source for a display device or a lighting device. In addition, when using the light-emitting device of this invention as a light source of an image display apparatus, using with a color filter is preferable. For example, when the image display device is a color image display device using a color liquid crystal display element, the light emitting device is used as a backlight, an optical shutter using liquid crystal, and a color filter having red, green, and blue pixels. By combining these, an image display device can be formed.

  An example of a surface emitting illumination device 12 incorporating the light emitting device 1 is schematically shown in FIG. In the surface light emitting illumination device 12, a large number of light emitting devices 1 are provided on the bottom surface of a rectangular holding case 13 whose inner surface is light-opaque such as a white smooth surface, and a power source for driving the light emitting device 1 is provided on the outside thereof. And a circuit (not shown) are provided. In order to make the light emission uniform, a diffuser plate 14 such as a milky white acrylic plate is fixed to a portion corresponding to the lid portion of the holding case 13.

  When the surface emitting illumination device 12 is used, the light emitting device 1 emits light. This light is transmitted through the diffusion plate 14 and emitted upward in the drawing, and illumination light with uniform brightness can be obtained within the surface of the diffusion plate 14 of the holding case 13.

EXAMPLES Hereinafter, although this invention is demonstrated still in detail using an Example, this invention is not limited to a following example, unless the summary is exceeded.
[Comparative Example 1]
2.091 g SrCO ₃ (Sr source), 0.501 g SiO ₂ (Si source), 0.440 g Eu ₂ O ₃ satisfying the stoichiometric ratio corresponding to Sr _0.85 Eu _0.15 Si ₂ O ₂ N ₂ (Eu source) and 1.169 g of Si ₃ N ₄ , ethanol was added to the slurry and mixed, and after natural drying, the resulting mixture was placed in an alumina crucible at 1400 ° C. under atmospheric pressure for 6 hours. Firing was performed. During this firing, nitrogen gas was flowed into the reactor at a flow rate of 3 L / min, and a mixed gas of 5% hydrogen and 95% of argon was flowed at a flow rate of 1 L / min. When the obtained product (phosphor of Comparative Example 1) was subjected to powder X-ray diffraction measurement, a powder X-ray diffraction pattern of SrSiO ₃ was included in addition to SrSi ₂ O ₂ N ₂ .

[Example 1]
Compositional formula {(Sr _1-x Ba _x ) _1-y Eu _y } ₂ 2.04 g of SrCO ₃ (Sr source) satisfying the stoichiometric ratio corresponding to x = 0, y = 0.15 in SiO ₄ , 0.501 g of SiO ₂ (Si source), and 0.440 g of Eu ₂ O ₃ (Eu source), add ethanol to form a slurry, and after air drying, the resulting mixture is placed in an alumina crucible. Then, primary firing was performed by firing at 950 ° C. under atmospheric pressure for 3 hours. During the primary firing, nitrogen gas was flowed into the reactor at a flow rate of 3 L / min and a mixed gas of 5% hydrogen and 95% of argon was flowed at a flow rate of 1 L / min.

The product obtained by the primary firing was subjected to powder X-ray diffraction measurement and analyzed for the composition. As a result, most of the product matched Sr ₂ SiO ₄ , but a small amount of Eu ₂ O ₃ remained. .
Next, 1.169 g of Si ₃ N ₄ was added to the product of primary firing so that (primary firing product): Si ₃ N ₄ : NH ₄ Cl = 1: 1: 0.05 (molar ratio). And 0.045 g of NH ₄ Cl was added and mixed, and the resulting mixture was placed in an alumina crucible and fired at 1400 ° C. under atmospheric pressure for 6 hours to perform secondary firing. Also during the secondary firing, the same mixed gas as in the primary firing was passed through the reaction furnace.

Powder X-ray diffraction measurement was performed on the product (phosphor of Example 1) obtained by secondary firing. The powder X-ray diffraction pattern of the phosphor of Example 1 obtained as a result is shown in FIG. In the powder X-ray diffraction pattern of the product (phosphor) after the secondary firing, no foreign phase such as a raw material was observed, and all the raw materials seemed to react. Therefore, the composition of the phosphor of Example 1 was Sr _0.85 Eu. It is considered to be _0.15 Si ₂ O ₂ N ₂ .

As is apparent from FIG. 4, the powder X-ray diffraction pattern of the phosphor of Example 1 has strong diffraction lines at three positions where the diffraction angle 2θ is about 12 °, about 25 °, and about 31 °.
Here, when the intensity of a diffraction line (reference diffraction line) having a diffraction angle 2θ of about 31 ° is 100%, the intensity of the diffraction line (first specific diffraction line) of about 25 ° which is the strongest line is 260%. The intensity of the diffraction line at about 12 ° (second specific diffraction line) is 50%.

These three diffraction lines are much stronger than any other diffraction lines. The strong diffraction line next to the diffraction line at about 12 ° (second specific diffraction line) exists at about 36 °, but its intensity is 42%, and the intensity of all other diffraction lines is 50% or less. .
In addition, although the crystal structure of the phosphor of Example 1 is layered, the diffraction lines at about 12 ° and about 25 ° are considered to be due to a plane parallel to the layer.

Moreover, about the fluorescent substance of Example 1 and Comparative Example 1, the emission spectrum at the time of exciting with the blue light of wavelength 460nm was measured with the following procedures.
The emission spectrum was measured using a 150 W xenon lamp as an excitation light source and a fluorescence measuring apparatus (manufactured by JASCO Corporation) equipped with a multi-channel CCD detector C7041 (manufactured by Hamamatsu Photonics) as a spectrum measuring apparatus. The light from the excitation light source was passed through a diffraction grating spectrometer having a focal length of 10 cm, and only the excitation light having a wavelength of 460 nm was irradiated to the phosphor through the optical fiber. The light generated from the phosphor by the irradiation of the excitation light is dispersed by a diffraction grating spectroscope having a focal length of 25 cm, the emission intensity of each wavelength is measured by a spectrum measuring device in a wavelength range of 300 nm to 800 nm, and a personal computer is used. An emission spectrum was obtained through signal processing such as sensitivity correction. During the measurement, the slit width of the light receiving side spectroscope was set to 1 nm and the measurement was performed.

The emission spectra of the phosphors of Example 1 and Comparative Example 1 obtained are shown in FIG. As is clear from FIG. 5, the phosphor of Example 1 showed the same emission spectrum as that of the phosphor of Comparative Example 1, but the emission peak intensity of the phosphor of Example 1 was the emission of the phosphor of Comparative Example 1. The peak intensity was 1.5 times. In addition, the half width of the emission peak of the phosphor of Example 1 was 84.5 nm.
[Example 2]
The product (phosphor of Example 2) was obtained by operating under the same conditions as in Example 1 except that NH ₄ Cl was not used in the procedure of Example 1.

When the obtained phosphor of Example 2 was subjected to powder X-ray diffraction measurement, the powder X-ray diffraction pattern was almost the same as FIG. Therefore, the composition of the phosphor of Example 2 is considered to be Sr _0.85 Eu _0.15 Si ₂ O ₂ N ₂ .
Further, when the emission spectrum of the phosphor of Example 2 was excited by blue light having a wavelength of 460 nm by the same procedure as that of Example 1, the emission peak intensity was the emission of the phosphor of Comparative Example 1. It was 1.3 times the peak intensity.

[Examples 3 to 6]
In the procedure of Example 1, operation was performed under the same conditions as in Example 1 except that the primary firing temperature was changed as shown in Table 2 below, and products (phosphors of Examples 3 to 6) were obtained.
Moreover, the composition of the product obtained after the primary firing was analyzed by powder X-ray diffraction measurement. The identification results of the composition of the product after the primary firing in Example 1 and Examples 3 to 6 are shown in Table 2 below.

Moreover, when the powder X-ray-diffraction measurement was performed about the product (phosphor of Examples 3-6) after secondary baking, the powder X-ray-diffraction pattern was substantially the same as FIG. Therefore, it is considered that the compositions of the phosphors of Examples 3 to 6 are all Sr _0.85 Eu _0.15 Si ₂ O ₂ N ₂ .
For the phosphors of Examples 3 to 6, emission spectra were measured when excited with blue light having a wavelength of 460 nm by the same procedure as in Example 1. The relative emission peak intensities of the phosphors of Example 1 and Examples 3 to 6 are shown in Table 2 below.

In addition, “relative emission peak intensity” of each example including the following is a phosphor for control (hereinafter referred to as “a phosphor” for reference) obtained by a one-step synthesis method under the same conditions as in each example, unless otherwise specified. The emission peak intensity is measured in the same procedure as in Example 1 using the “one-step synthetic control phosphor”), and the ratio is shown as the ratio when the emission peak of the obtained control phosphor is 100%.
In Example 1 and Examples 3 to 6, the phosphor of Comparative Example 1 was used as the one-step synthetic control phosphor.

[Examples 7 to 11]
SrCO ₃ , BaCO ₃ , SiO ₂ satisfying the stoichiometric ratio corresponding to x = 0.25 and y = 0.15 in the compositional formula {(Sr _1−x Ba _x ) _1−y Eu _y } ₂ SiO ₄ , And Eu ₂ O ₃ , ethanol is added to form a slurry, and after natural drying, the resulting mixture is placed in an alumina crucible and at atmospheric pressure at the temperature shown in Examples 7 to 11 of Table 3 described later. The primary baking was performed by baking for 3 hours. During the primary firing, the same mixed gas as in Example 1 was flowed into the reaction furnace. Moreover, the powder X-ray-diffraction measurement of the product obtained by primary baking was performed, and the composition was analyzed. The identification results are shown in Table 3 below.

Next, Si ₃ N ₄ and NH ₄ Cl are added to the product of the primary firing so that (the product of the primary firing): Si ₃ N ₄ : NH ₄ Cl = 1: 1: 0.05 (molar ratio). In addition, the mixture was made into a slurry form and naturally dried. After that, the obtained mixture was placed in an alumina crucible and fired at 1400 ° C. under atmospheric pressure for 6 hours to perform secondary firing. Also during the secondary firing, the same mixed gas as in Example 1 was allowed to flow into the reaction furnace.

Powder X-ray diffraction measurement was performed on the secondary firing product (phosphors of Examples 7 to 11). In the obtained powder X-ray diffraction pattern, no foreign phase such as a raw material was observed, and all the raw materials seemed to react. Therefore, the composition of the product (phosphors of Examples 7 to 11) was ( Sr _0.75 Ba _0.25 ) _0.85 Eu _0.15 Si ₂ O ₂ N ₂ .
The powder X-ray diffraction pattern of the phosphor of Example 8 is shown in FIG.

As is apparent from FIG. 6, the powder X-ray diffraction pattern of the phosphor of Example 8 has strong diffraction lines at three positions where the diffraction angle 2θ is about 12 °, about 25 °, and about 31 °.
Here, assuming that the intensity of a diffraction line (reference diffraction line) having a diffraction angle 2θ of about 31 ° is 100%, the intensity of a diffraction line (first specific diffraction line) of about 25 ° which is the strongest line is 625%. The intensity of the diffraction line at about 12 ° (second specific diffraction line) is 225%.

These three diffraction lines are much stronger than any other diffraction lines. The strong diffraction line next to the diffraction line at about 12 ° (second specific diffraction line) exists at about 36 °, but its intensity is 42%, and the intensity of all other diffraction lines is 50% or less. .
The crystal structure of the phosphor of Example 8 is layered, but the diffraction lines of about 12 ° and about 25 ° are considered to be due to a plane parallel to the layer.

In addition, for the phosphors of Examples 7 to 11, emission spectra when excited with blue light having a wavelength of 460 nm were measured by the same procedure as in Example 1. The relative emission peak intensities of the phosphors of Examples 7 to 11 are shown in Table 3 below.
In addition, as a one-step synthetic control phosphor for determining the relative emission peak intensities of Examples 7 to 11, the same procedure as in Comparative Example 1 was used except that the composition ratio of the raw materials was the same as in Examples 7 to 11. The obtained phosphor was used.

In addition, the fluorescence measurement apparatus provided with a 150 W xenon lamp as an excitation light source and a multichannel CCD detector C7041 (manufactured by Hamamatsu Photonics) as a spectrum measurement apparatus under the temperature condition of 25 ° C. for the excitation spectrum of the phosphor of Example 8. It was measured using (manufactured by JASCO Corporation).
The excitation spectrum of the obtained phosphor of Example 8 at an emission wavelength of 550 nm is shown in FIG. 7 together with the excitation spectrum of Y ₃ Al ₅ O ₁₂ : Ce at an emission wavelength of 550 nm. As is clear from FIG. 7, the phosphor of Example 8 always has a light emission intensity of a certain level or higher even when excited with light of any wavelength within the wavelength range of 234 to 470 nm. From this, it can be seen that the phosphor of the present invention does not change its green / green-yellow emission intensity even when excited with light of any wavelength indicated by the near ultraviolet to blue LEDs.

[Examples 12 to 14]
In the procedure of Example 8, except that the secondary firing temperature was changed as shown in Table 4 below, the operation was performed under the same conditions as in Example 8 to obtain products (phosphors of Examples 12 to 14). .
Phase identification of the phosphors of Examples 12 to 14 was performed by powder X-ray diffraction measurement. The identification results are shown in Table 4 below. The phosphors of Example 12 and Example 13 are a mixture of the target product (Sr _0.75 Ba _0.25 ) _0.85 Eu _0.15 Si ₂ O ₂ N ₂ and (Sr _0.75 Ba _0.25 ) ₂ SiO ₄ : Eu. Conceivable. On the other hand, the phosphor of Example 14 is considered to be a single phase of (Sr _0.75 Ba _0.25 ) _0.85 Eu _0.15 Si ₂ O ₂ N ₂ which is the target product.

In addition, with respect to the phosphors of Examples 12 to 14, emission spectra when excited with blue light having a wavelength of 460 nm were measured by the same procedure as in Example 1. The relative emission peak intensities of the phosphors of Example 8 and Examples 12 to 14 are shown in Table 4 below.
In addition, as a one-step synthetic control phosphor for obtaining the relative emission peak intensities of Examples 12 to 14, the composition ratio of the raw materials is set to be the same as that of Examples 12 to 14, and the firing time is the secondary firing time of Examples 12 to 14. A phosphor obtained by the same procedure as in Comparative Example 1 was used except that the procedure was the same.

[Examples 15 to 17]
In the general formula {(Sr _1−x Ba _x ) _1−y Eu _y } ₂ SiO ₄ , y is fixed at 0.15, and x is changed as shown in Table 5 to be described later. The product (phosphors of Examples 15 to 17) was operated under the same conditions as in Example 1 except that raw materials (SrCO ₃ , BaCO ₃ , SiO ₂ , Eu ₂ O ₃ ) in a ratio satisfying the ratio were used. )

Phase identification of the phosphors of Examples 15 to 17 was performed by powder X-ray diffraction measurement. The identification results are shown in Table 5 below. The compositions of the phosphors of Examples 15 to 17 were (Sr _0.50 Ba _0.50 ) _0.85 Eu _0.15 Si ₂ O ₂ N ₂ , (Sr _0.25 Ba _0.75 ) _0.85 Eu _0.15 Si ₂ O ₂ N ₂ , and Ba _0.85 Eu _0.15 Si. ₂ O ₂ N ₂ is considered.
In addition, with respect to the phosphors of Examples 15 to 17, emission spectra when excited with blue light having a wavelength of 460 nm were measured by the same procedure as in Example 1. Table 5 below shows the relative emission peak intensities of the phosphors of Example 1, Example 8, and Examples 15-17.

  In addition, as a one-step synthetic control phosphor for obtaining the relative emission peak intensities of the phosphors of Examples 15 to 17, the same composition ratio of the raw materials as in Examples 15 to 17 was used, and the same as in Comparative Example 1 above. The phosphor obtained by the procedure was used.

[Examples 18 to 21]
In the general formula {(Sr _1−x Ba _x ) _1−y Eu _y } ₂ SiO ₄ , x is fixed at 0.25, and x is changed as shown in Table 6 to be described later. The product (phosphors of Examples 18 to 21) was operated under the same conditions as in Example 8 except that raw materials (SrCO ₃ , BaCO ₃ , SiO ₂ , Eu ₂ O ₃ ) satisfying the ratio were used. )

In addition, with respect to the phosphors of Examples 18 to 21, emission spectra when excited with blue light having a wavelength of 460 nm were measured by the same procedure as in Example 1.
For the phosphors of Example 1 and Examples 18 to 21, the relative emission peak intensity when the emission peak intensity of the phosphor of Example 18 (y = 0.01) is 100%, and the one-step synthesized control phosphor Table 6 below shows the relative light emission peak intensities with reference to.

  In addition, as a one-step synthetic control phosphor for obtaining the relative emission peak intensities of the phosphors of Examples 18 to 21, the same composition ratio of the raw materials as in Examples 18 to 21 was used, and the same as in Comparative Example 1 above. The phosphor obtained by the procedure was used.

[Example 22]
(Primary firing)
Formula _{Sr 1.4 Ba 0.5 Eu 0.1 SiO 4} (= (Sr 0.74 Ba 0.26) 1.9 Eu 0.1 SiO 4) so that, SrCO ₃ (Shirotatsu Chemical Co., purity 98%) and 5.37 g, BaCO ₃ ( 2.58 g of Shirakaba Chemical Co., Ltd., purity 98%), 0.48 g of Eu ₂ O ₃ (Shin-Etsu Chemical Co., Ltd., purity 99.99%), SiO ₂ (manufactured by Tatsumori Co., Ltd., 99.99%) Each 1.57 g was weighed and sufficiently wet mixed in an alumina mortar. Subsequently, the mixed raw material powder having a particle size of 250 μm or less was collected by sieving and closely packed in an alumina crucible. This alumina crucible was placed in a resistance-heated tubular electric furnace with temperature control, and from atmospheric temperature to 110 ° C. in a mixed air flow of 96 vol% nitrogen + 4 vol% hydrogen at a flow rate of 0.5 l / min. At a rate of 94 ° C / min, 1 ° C / min from 110 ° C to 200 ° C, 4.6 ° C / min from 200 ° C to 800 ° C, then 4.5 ° C / min from 800 ° C to 1250 ° C Heated and held at that temperature for 3 hours. After firing, the mixture was allowed to cool to room temperature, taken out, and pulverized and mixed in an alumina mortar.

(Secondary firing)
Next, 7.6 g of the primary firing product, 3.6 g of α-Si ₃ N ₄ (manufactured by Ube Industries, SN-E10) and NH ₄ Cl (manufactured by Kanto Chemical Co., Inc., purity 99.0%) ) 0.08 g (0.67% by weight) was weighed and wet-mixed in an alumina mortar, and a powder having a particle size of 250 μm or less was separated from this mixed powder by sieving and closely packed in an alumina mortar. . This alumina crucible was placed in a resistance-heating tubular electric furnace with temperature control, and from atmospheric temperature to 120 ° C. in a mixed gas stream of 96 vol% nitrogen + 4 vol% hydrogen at a flow rate of 0.5 l / min. At a rate of temperature increase of 05 ° C / min, 0.89 ° C / min from 120 ° C to 200 ° C, 4.6 ° C / min from 200 ° C to 800 ° C, then 4.3 ° C / min from 800 ° C to 1450 ° C Heated in minutes and held at that temperature for 8 hours. After firing, the mixture was allowed to cool to room temperature, and this was taken out and pulverized and mixed in an alumina mortar to obtain Sr _0.7 Ba _0.25 Eu _0.05 Si ₂ O ₂ N ₂ . Table 7 shows the emission characteristics of this phosphor. Here, the relative peak intensity and the relative luminance indicate relative values when the values when P46-Y3 manufactured by Kasei Optonics Co., Ltd. is excited with light having a wavelength of 455 nm are set to 100, respectively.

[Example 23]
In (secondary firing) of Example 22, the α-Si ₃ N _4, except for using the α-Si ₃ N ₄ heat-treated β-Si ₃ N ₄ were obtained in place of similarly phosphor Obtained. Table 7 shows the emission characteristics of this phosphor.

[Examples 24 and 25]
In (secondary firing) of Example 22, β-Si ₃ N ₄ was used instead of α-Si ₃ N ₄ , and the firing temperature was 1500 ° C. (Example 24) or 1550 ° C. (Example 25), respectively. A phosphor was obtained in the same manner as in Example 22 except that. The emission characteristics of this phosphor are shown in Table 8.

[Example 26]
In (primary firing), the carbon dioxide gas generated by the thermal decomposition of the carbonate corrodes the heating element of the reducing atmosphere furnace, so the firing furnace of (primary firing) is a box electric furnace (manufactured by Motoyama, RH-2035D ), At atmospheric pressure, from room temperature to 110 ° C., at a rate of 0.94 ° C./min, from 110 ° C. to 200 ° C., 1 ° C./min, from 200 ° C. to 800 ° C., 4.6 ° C./min And then heated from 800 ° C. to 1250 ° C. at 4.5 ° C./min and held at that temperature for 3 hours. After firing, the mixture was allowed to cool to room temperature, taken out, and pulverized and mixed in an alumina mortar. Next, a fired product was obtained in the same manner as in Example 25 except that the firing time of (secondary firing) was set to 4 hours. This was taken out, ground in an alumina mortar, and stirred in 1N hydrochloric acid for 15 minutes. After stirring, the supernatant was discarded and the residue was washed with water and dried to obtain a phosphor. Table 9 shows the light emission characteristics of this phosphor. Thus, it can be seen that a phosphor having similar characteristics can be obtained even when the firing atmosphere of the primary firing is changed.

[Examples 27 to 30]
Instead of NH ₄ Cl used as a fluxing agent for (secondary firing), 0.11 g (0.87 wt%) ZnCl ₂ (Example 27) and 0.12 g (1.00 wt%) SrCl, respectively. ₂ (Example 28), Example 26 except that 0.03 g (0.27 wt%) NaF (Example 29) or 0.08 g (0.69 wt%) ZnF ₂ (Example 30) was used. In the same manner as above, a phosphor was obtained. Table 10 shows the characteristics of this phosphor.

In addition, with respect to the phosphors of Examples 25 to 30, Table 11 shows the measurement results of the respective quantum efficiencies (internal, absorption, external) measured by the following method.
[Measurement method of absorption efficiency, internal quantum efficiency, and external quantum efficiency]
The absorption efficiency αq, internal quantum efficiency ηi, and external quantum efficiency ηo of the phosphor were determined as follows.

First, the phosphor sample to be measured was packed in a cell with a sufficiently smooth surface so that the measurement accuracy was maintained, and was attached to an integrating sphere.
Light was introduced into this integrating sphere from an emission light source (150 W Xe lamp) for exciting the phosphor using an optical fiber. The emission peak wavelength of light from the light emission source was adjusted using a monochromator (diffraction grating spectrometer) or the like so as to be monochromatic light of 455 nm. Using this monochromatic light as excitation light, the phosphor sample to be measured was irradiated, and the spectrum was measured for the emission (fluorescence) and reflected light of the phosphor sample using a spectrometer (MCPD7000 manufactured by Otsuka Electronics Co., Ltd.). The light in the integrating sphere was guided to a spectroscopic measurement device using an optical fiber.

The absorption efficiency αq is a value obtained by dividing the number of photons _Nabs of excitation light absorbed by the phosphor sample by the total number of photons N of excitation light.
First, the total number of photons N of the latter excitation light is proportional to the numerical value obtained by the following (formula A). Therefore, a “Spectralon” manufactured by Labsphere (having a reflectance R of 98% with respect to the excitation light having a wavelength of 450 nm), which is a reflector having a reflectance R of almost 100% with respect to the excitation light, is measured. A reflection spectrum I _ref (λ) was measured by attaching to the integrating sphere with the same arrangement as the phosphor sample, irradiating with excitation light, and measuring with a spectroscopic measurement device, and the value of the following (formula A) was obtained. .

Here, the integration interval was 410 nm to 480 nm.
The number N _abs of the photons in the excitation light that is absorbed in the phosphor sample is proportional to the amount calculated by the following equation (B).

  Therefore, the reflection spectrum I (λ) was obtained when the phosphor sample for which the absorption efficiency αq is to be obtained was attached. The integration range of (Formula B) was the same as the integration range defined in (Formula A). Since the actual spectrum measurement value is generally obtained as digital data divided by a certain finite bandwidth with respect to λ, the integration of (Equation A) and (Equation B) was obtained by the sum based on the bandwidth. .

From the above, αq = _Nabs / N = (Formula B) / (Formula A) was calculated.
Next, the internal quantum efficiency ηi was determined as follows. Internal quantum efficiency ηi is a value obtained by dividing the number N _abs of photons number N _PL of photons originating from the fluorescence phenomenon absorbed by the phosphor sample.
Here, N _PL is proportional to the amount obtained by the following (formula C). Therefore, the amount required by the following (formula C) was determined.

The integration interval was 481 nm to 800 nm.
As described above, ηi = (formula C) / (formula B) was calculated, and the internal quantum efficiency ηi was obtained.
It should be noted that the integration from the spectrum that was converted to digital data was performed in the same manner as when the absorption efficiency αq was obtained.
And the external quantum efficiency (eta) o was calculated | required by taking the product of absorption efficiency (alpha) q calculated | required as mentioned above and internal quantum efficiency (eta) i.

The use of the phosphor of the present invention is not particularly limited, and can be used in various fields where ordinary phosphors are used, but takes advantage of its excellent conversion efficiency and color purity for blue light or near ultraviolet light. Therefore, it is suitable for the purpose of realizing a general illuminant that is excited by a light source such as a near-ultraviolet LED or a blue LED, particularly a white illuminant for a backlight having a high luminance and a wide color reproduction range.
Further, the light emitting device of the present invention using the phosphor of the present invention having the above-described characteristics can be used in various fields where a normal light emitting device is used. And particularly preferably used.

It is typical sectional drawing which shows the light-emitting device which concerns on one Embodiment of this invention. It is a typical perspective view which shows other embodiment of the light-emitting device of this invention. It is a schematic cross section which shows an example of the surface emitting illumination apparatus using the light-emitting device of this invention. 2 is a powder X-ray diffraction pattern of the phosphor of Example 1. FIG. It is an emission spectrum of the phosphors of Example 1 and Comparative Example 1. 7 is a powder X-ray diffraction pattern of the phosphor of Example 8. FIG. It is the excitation spectrum of the phosphor of Example 8 and Y ₃ Al ₅ O ₁₂ : Ce.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Light-emitting device 2 Frame 2A The recessed part of a frame 3 Blue LED (1st light-emitting body)
4 Phosphor-containing part (second light emitter)
5 Silver paste 6 Wire 7 Mold part 8 Light-emitting device 9 Substrate 10 Surface-emitting GaN-based LD (first light emitter)
DESCRIPTION OF SYMBOLS 11 2nd light-emitting body 12 Surface emitting illuminating device 13 Holding case 14 Diffusion plate

Claims (16)

A method for producing a phosphor made of oxysilicon nitride,
A method for producing a phosphor, comprising a step of mixing silicate and Si ₃ N ₄ and firing in a reducing atmosphere. The method for producing a phosphor according to claim 1, wherein the oxysilicon nitride has a composition represented by the following general formula [1].

(In the general formula [1],
M ^I represents one or more metal elements that can have a divalent and / or trivalent valence other than Sr.
M ^II represents one or more rare earth elements.
x and y represent numbers satisfying 0 ≦ x ≦ 1 and 0 <y ≦ 1, respectively. ) The method for producing a phosphor according to claim 1 or 2, wherein the silicate has a composition represented by the following general formula [2].

(In the general formula [2],
M ^I represents one or more metal elements that can have a divalent and / or trivalent valence other than Sr.
M ^II represents one or more rare earth elements.
x and y represent numbers satisfying 0 ≦ x ≦ 1 and 0 <y ≦ 1, respectively. ) 4. The method according to claim 3, further comprising the step of obtaining a silicate having the composition of the general formula [2] by mixing and firing at least a M ^I source, a M ^II source, and a Si source. A method for manufacturing the phosphor. The method for producing a phosphor according to claim 1, wherein a flux is used during firing. While having the composition represented by the following general formula [1],
In the powder X-ray diffraction pattern using CuKα X-rays, when the diffraction angle 2θ is 30 ° or more and 33 ° or less and the intensity of the strongest diffraction line is 100%,
The intensity of the highest intensity diffraction line existing at a diffraction angle 2θ of 11 ° or more and 14 ° or less is 50% or more,
The intensity of the highest intensity diffraction line existing at a diffraction angle 2θ of 23 ° or more and 27 ° or less is 200% or more,
A phosphor having an intensity of other diffraction lines of 50% or less.

(In the general formula [1],
M ^I represents one or more metal elements that can have a divalent and / or trivalent valence other than Sr.
M ^II represents one or more rare earth elements.
x and y represent numbers satisfying 0 ≦ x ≦ 1 and 0 <y ≦ 1, respectively. ) The phosphor according to claim 6, wherein x is less than 1 in the general formula [1]. The phosphor according to claim 6 or 7, wherein in the general formula [1], M ^II contains at least Eu. A phosphor-containing composition comprising the phosphor according to any one of claims 6 to 8 and a liquid medium. A first light emitter, and a second light emitter that emits visible light by irradiation of light from the first light emitter,
A light emitting device, wherein the second light emitter contains at least one or more kinds of the phosphors according to any one of claims 6 to 8 as a first phosphor. The light emitting device according to claim 10, wherein the second phosphor includes at least one phosphor having a light emission wavelength different from that of the first phosphor as the second phosphor. . The first light emitter has a light emission peak in a wavelength range of 420 nm to 500 nm;
The light emitting device according to claim 11, wherein the second phosphor includes at least one phosphor having an emission peak in a wavelength range of 570 nm to 680 nm as the second phosphor. The first light emitter has a light emission peak in a wavelength range of 300 nm or more and 420 nm or less;
The second phosphor is, as the second phosphor, at least one phosphor having an emission peak in a wavelength range of 420 nm to 490 nm and at least one having an emission peak in a wavelength range of 570 nm to 680 nm. The light emitting device according to claim 11, further comprising a phosphor. The first light emitter has a light emission peak in a wavelength range of 420 nm to 500 nm;
The light emitting device according to claim 11, wherein the second phosphor includes at least one phosphor having an emission peak in a wavelength range of 580 nm to 620 nm as the second phosphor. . An image display device comprising the light-emitting device according to claim 10 as a light source. An illuminating device comprising the light emitting device according to claim 10 as a light source.

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